Rail gauge
Encyclopedia
Track gauge or rail gauge is the distance between the inner sides of the heads of the two load bearing rails
Rail profile
The rail profile is the cross sectional shape of a railway rail, perpendicular to the length of the rail.In all but very early cast iron rails, a rail is hot rolled steel of a specific cross sectional profile designed for use as the fundamental component of railway track.Unlike some other uses of...

 that make up a single railway line
Rail tracks
The track on a railway or railroad, also known as the permanent way, is the structure consisting of the rails, fasteners, sleepers and ballast , plus the underlying subgrade...

. Sixty percent of the world's railways use a standard gauge
Standard gauge
The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

 of . Wider gauges are called broad gauge
Broad gauge
Broad-gauge railways use a track gauge greater than the standard gauge of .- List :For list see: List of broad gauges, by gauge and country- History :...

; smaller gauges, narrow gauge. Break-of-gauge
Break-of-gauge
With railways, a break-of-gauge occurs where a line of one gauge meets a line of a different gauge. Trains and rolling stock cannot run through without some form of conversion between gauges, and freight and passengers must otherwise be transloaded...

 refers to the meeting of different gauges. Some stretches of track are dual gauge
Dual gauge
A dual-gauge or mixed-gauge railway has railway track that allows trains of different gauges to use the same track. Generally, a dual-gauge railway consists of three rails, rather than the standard two rails. The two outer rails give the wider gauge, while one of the outer rails and the inner rail...

, with three or four rails, allowing trains of different gauges to share them. Gauge conversion
Gauge conversion
In rail transport, gauge conversion is the process of converting a railway from one rail gauge to another, through the alteration of the railway tracks...

 can resolve break-of-gauge problems. An exception of a railway with no gauge is monorail
Monorail
A monorail is a rail-based transportation system based on a single rail, which acts as its sole support and its guideway. The term is also used variously to describe the beam of the system, or the vehicles traveling on such a beam or track...

 where there is only one supporting rail. Some electrified railways use non load bearing third rail
Third rail
A third rail is a method of providing electric power to a railway train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost...

 and occasionally a fourth rail. These additional rails are positioned between or outside the 'running rails' to feed and return electrical current, they do not define the rail gauge.

Gauge tolerances specify how much the actual gauge may vary from the nominal gauge. For example, the U.S. Federal Railroad Administration
Federal Railroad Administration
The Federal Railroad Administration is an agency in the United States Department of Transportation. The agency was created by the Department of Transportation Act of 1966...

 specifies that the actual gauge of track that is rated for a maximum of 60 mph (96.6 km/h) must be between and .

A track gauge is also the name of the measuring device used to test whether rails are within the correct gauge.

Overview

New railways, especially recent high speed rail (AVE
AVE
Alta Velocidad Española is a service of high-speed rail in Spain operated by Renfe, the Spanish national railway company, at speeds of up to . The name is literally translated from Spanish as "Spanish High Speed", but also a play on the word , meaning "bird".AVE trains run on a network of...

 and Shinkansen
Shinkansen
The , also known as THE BULLET TRAIN, is a network of high-speed railway lines in Japan operated by four Japan Railways Group companies. Starting with the Tōkaidō Shinkansen in 1964, the network has expanded to currently consist of of lines with maximum speeds of , of Mini-shinkansen with a...

), are usually built to standard gauge. Advantages are:
  • It facilitates inter-running with neighbouring railways
  • Locomotive
    Locomotive
    A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...

    s and rolling stock
    Rolling stock
    Rolling stock comprises all the vehicles that move on a railway. It usually includes both powered and unpowered vehicles, for example locomotives, railroad cars, coaches and wagons...

     can be ordered from manufacturers' standard designs and do not need to be custom built, though some adaptation to local conditions may be necessary, for example, regarding loading gauge
    Loading gauge
    A loading gauge defines the maximum height and width for railway vehicles and their loads to ensure safe passage through bridges, tunnels and other structures...

    .


Generally speaking, of the gauges between and 1700 millimetre, standard gauge works well enough. The supposed advantages of broader or narrower gauges in this range are not enough to overcome the disadvantages of any break of gauge in a railway system.

Dominant gauges




Gauge Name Installation (km) Installation (miles) Usage
Indian gauge
Indian gauge
Indian gauge is a track gauge commonly used in India, Pakistan, Bangladesh, Sri Lanka, Argentina and Chile. It is also the gauge that is used on BART , in northern California.- Scotland :...

7850048,777.8 India
Rail transport in India
Rail transport is a commonly used mode of long-distance transportation in India. Almost all rail operations in India are handled by a state-owned organisation, Indian Railways, Ministry of Railways. The rail network traverses the length and breadth of the country, covering a total length of...

 (42000 km (26,097.7 mi); increasing with Project Unigauge
Project Unigauge
Project Unigauge is an ongoing exercise by Indian Railways to standardise most of the rail gauges in India at 1676 mm broad gauge....

), Pakistan, Argentina
Rail transport in Argentina
The Argentine railway network comprised of track at the end of the Second World War and was, in its time, one of the most extensive and prosperous in South America. However, with the increase in highway construction, there followed a sharp decline in railway profitability, leading to the break-up...

 24000 km (14,912.9 mi), Chile, Sri Lanka
Sri Lanka Railways
Sri Lanka Railway Department, branded "Sri Lanka Railways", is a key department of the Sri Lankan Government under the Ministry of Transport with a history that begins in 1858...

 1508 km (937 mi)
(approx. 6.67% of the world's railways)
Iberian gauge
Iberian gauge
Iberian gauge is the name given to the track gauge most extensively used by the railways of Spain and Portugal: namely ....

153949,565.4 Portugal, Spain. In Spain as of the Iberian gauge 21 km (13 mi) are of three-rail dual Iberian and standard gauges, more to come in the future
Irish gauge
Irish gauge
Irish gauge railways use a track gauge of . It is used in* Ireland * Australia where it is also known as Victorian Broad Gauge* Brazil where it is also known as Bitola larga no Brasil....

98006,089.5 Ireland (1800 km (1,118.5 mi)), and in Australia mainly Victoria and some South Australia Victorian gauge (4017 km (2,496.1 mi)), Brazil
Rail transport in Brazil
Rail transport in Brazil began in the 19th century and there were many different railway companies. The railways were nationalised under RFFSA in 1957...

 (4057 km (2,520.9 mi))
Russian gauge
Russian gauge
In railway terminology, Russian gauge refers to railway track with a gauge between 1,520 mm and . In a narrow sense as defined by Russian Railways it refers to gauge....

58653,644.4 Finland
Rail transport in Finland
The Finnish railway network consists of a total of 5,919 km of railways built with Russian gauge track. Passenger trains are operated by the private state-owned VR Group. They serve all the major cities and many rural areas, though railway connections are available to fewer places than bus...

 (contiguous to and generally compatible with )
Russian gauge
Russian gauge
In railway terminology, Russian gauge refers to railway track with a gauge between 1,520 mm and . In a narrow sense as defined by Russian Railways it refers to gauge....

220000136,702 CIS states, also Estonia
Rail transport in Estonia
The rail transport system in Estonia consists of circa of railway lines, of which are currently in public use. The infrastructure of the railway network is mostly owned by the state and is regulated and surveyed by the Estonian Railway Inspectorate ....

, Georgia, Latvia
Rail transport in Latvia
Rail transport in Latvia is done on Russian gauge. The main railway company is Latvijas dzelzceļš.Historically Latvia had lot of different rail gauges, most notably standard gauge and narrow gauge.- Rail links with adjacent countries :...

, Lithuania, Mongolia
Rail transport in Mongolia
Rail transport in Mongolia is an important means of travel in the landlocked nation with few paved roads. According to official statistics, rail transport carried 93% of Mongolian freight and 43% of passenger turnover in 2007. The Mongolian rail system employs 12,500 people. The national operator...


(approx. 17% of the world's railways; all contiguous — redefined from )
720000447,388.4 Europe
Rail transport in Europe
Rail transport in Europe is characterised by its diversity, both technical and infrastructural.Rail networks in Western and Central Europe are often well maintained and well developed, whilst Eastern and Southern Europe often have less coverage and infrastructure problems...

, Argentina
Rail transport in Argentina
The Argentine railway network comprised of track at the end of the Second World War and was, in its time, one of the most extensive and prosperous in South America. However, with the increase in highway construction, there followed a sharp decline in railway profitability, leading to the break-up...

, United States
Rail transport in the United States
Presently, most rail transport in the United States is based on freight train shipments. The U.S. rail industry has experienced repeated convulsions due to changing U.S. economic needs and the rise of automobile, bus, and air transport....

, Canada
Rail transport in Canada
Canada has a large and well-developed railway system that today transports primarily freight. There are two major privately owned transcontinental freight railway systems, the Canadian National and Canadian Pacific Railway. Nation-wide passenger services are provided by the federal crown...

, China
Rail transport in the People's Republic of China
Rail transport is the most commonly used mode of long-distance transportation in the People's Republic of China. Almost all rail operations are handled by the Ministry of Railways, which is part of the State Council of the People's Republic of China...

, Korea (South)
Rail transport in South Korea
The rail transportation system in South Korea includes mainline railway lines, and rapid transit system in some major cities.- Korean Empire and Partition :...

, Korea (North)
Rail transport in North Korea
Rail transport in North Korea is provided by Korean State Railway which is the only rail operator in North Korea. It has a network of 5,200 km of track with 4,500 km in Standard gauge. There is a small narrow gauge railway in operation in Haeju peninsula...

, Australia
Rail transport in Australia
Rail transport in Australia is a crucial aspect of the Australian transport network, and an enabler of the wider Australian economy. Rail in Australia is to a large extent state-based. The Australian rail network consists of a total of 41,461 km of track of three major gauges, of which...

, Middle East, North Africa, Mexico
Rail transport in Mexico
Mexico has a freight railway system that is privately owned and extends across most of the country, connecting major industrial centers with ports and with rail connections at the United States border...

, Cuba, Panama
Rail transport in Panama
Since 1974, the only functioning railroad in Panama is Panama Canal Railway Company, successor of Panama Railway - the oldest transcontinental railroad in the world. It provides passenger and freight service between Panama City and Colón...

, Venezuela, Peru
Rail transport in Peru
Rail transport in Peru has never consisted of a true network, primarily comprising separate lines running inland from the coast.Many of the lines owe their origins to contracts granted to United States entrepreneurs Henry Meiggs and W. R. Grace and Company but the mountainous nature of Peru made...

, Uruguay
Rail transport in Uruguay
The Uruguayan railway network has approximately 2900 km of lines, all of gauge 1435 mm, diesel traction and only 11 km of double track...

 and Philippines
Rail transport in the Philippines
Rail transport in the Philippines is a growing means of transportation for passengers and cargo in the country. Such means of transportation are used typically for rapid transport within major cites as well as long distance travel...

. Also high-speed lines in Japan
Rail transport in Japan
Rail transport in Japan is a major means of passenger transport, especially for mass and high-speed travel between major cities and for commuter transport in metropolitan areas.-Overview:...

 and Spain.
(approx. 60% of the world's railways)
Cape gauge
Cape gauge
Cape gauge is a track gauge of between the inside of the rail heads and is classified as narrow gauge. It has installations of around .The gauge was first used by Norwegian engineer Carl Abraham Pihl and the first line was opened in 1862.- Nomenclature :...

11200069,593.7 Southern and Central Africa, Indonesia
Rail transport in Indonesia
Most rail transport in Indonesia is located on the island of Java, which has two major rail lines that run the length of the island, as well as several connecting lines...

, Japan, Taiwan
Rail transport in Taiwan
Taiwan has an extensive network of railways . Though no longer as dominant as it once was, Taiwan's high population density continues to make rail transport an extremely important form of transportation, especially along the densely populated western corridor...

, Philippines
Rail transport in the Philippines
Rail transport in the Philippines is a growing means of transportation for passengers and cargo in the country. Such means of transportation are used typically for rapid transport within major cites as well as long distance travel...

, New Zealand
Rail transport in New Zealand
Rail transport in New Zealand consists of a network of gauge railway lines in both the North and South Islands. Rail services are focused primarily on freight, particularly bulk freight, with limited passenger services on some lines...

, Queensland Australia Queensland Rail
Queensland Rail
Queensland Rail, also known as QR, is a government-owned railway operator in the state of Queensland. Under the control of the Queensland Government, Queensland Rail operates the inner-city and long-distance passenger services, as well as some freight operations and gives railway access to other...

 
(approx. 9% of the world's railways)
Metre gauge
Metre gauge
Metre gauge refers to narrow gauge railways and tramways with a track gauge of . In some African, American and Asian countries it is the main gauge. In Europe it has been used for local railways in France, Germany, and Belgium, most of which were closed down in mid 20th century. Only in Switzerland...

9500059,030.4 SE Asia, India (17000 km (10,563.3 mi), decreasing with Project Unigauge
Project Unigauge
Project Unigauge is an ongoing exercise by Indian Railways to standardise most of the rail gauges in India at 1676 mm broad gauge....

), Argentina
Rail transport in Argentina
The Argentine railway network comprised of track at the end of the Second World War and was, in its time, one of the most extensive and prosperous in South America. However, with the increase in highway construction, there followed a sharp decline in railway profitability, leading to the break-up...

 (11000 km (6,835.1 mi)), Brazil
Rail transport in Brazil
Rail transport in Brazil began in the 19th century and there were many different railway companies. The railways were nationalised under RFFSA in 1957...

 (23489 km (14,595.4 mi)), Bolivia
Rail transport in Bolivia
The Bolivian rail network has had a peculiar development throughout its history, owing to losses of land, prestige and credit rating due to the failure of the War of the Pacific, railway development came late to Bolivia. The demand for mineral wealth and communication to the inland city of La Paz,...

, northern Chile, Switzerland
Rail transport in Switzerland
The railways of Switzerland include and narrow gauge .*Network size: 5,063 km*standard gauge: , of which is electrified.*narrow gauge: , of which is electrified...

 (RhB, MOB, BOB, MGB), East Africa
(approx. 7% of the world's railways)

History

Historically, the choice of gauge was partly arbitrary and partly a response to local conditions. Narrow-gauge railways are cheaper to build and can negotiate sharper curves but broad-gauge railways give greater stability and permit higher speeds.

Sometimes railway companies chose their own gauge, such as the Great Western Railway
Great Western Railway
The Great Western Railway was a British railway company that linked London with the south-west and west of England and most of Wales. It was founded in 1833, received its enabling Act of Parliament in 1835 and ran its first trains in 1838...

 choosing .

Other times, statutes required railways to use a particular gauge, such as the Thomasville, Tallahassee and Gulf Railroad
Thomasville, Tallahassee and Gulf Railroad
The Thomasville, Tallahassee and Gulf Railroad was incorporated under the general incorporation laws of Florida to build, maintain, and operate a railroad from a point on the line between the cities of Tallahassee, in the State of Florida, and Thomasville, in the State of Georgia, through the...

 having to use standard gauge
Standard gauge
The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

.

Early origins of the standard gauge

There is an urban legend
Urban legend
An urban legend, urban myth, urban tale, or contemporary legend, is a form of modern folklore consisting of stories that may or may not have been believed by their tellers to be true...

 that Julius Caesar
Julius Caesar
Gaius Julius Caesar was a Roman general and statesman and a distinguished writer of Latin prose. He played a critical role in the gradual transformation of the Roman Republic into the Roman Empire....

 specified a legal width for chariot
Chariot
The chariot is a type of horse carriage used in both peace and war as the chief vehicle of many ancient peoples. Ox carts, proto-chariots, were built by the Proto-Indo-Europeans and also built in Mesopotamia as early as 3000 BC. The original horse chariot was a fast, light, open, two wheeled...

s at the width of standard gauge
Standard gauge
The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

, causing road ruts
Rut (roads)
A rut is a depression or groove worn into a road or path by the travel of wheels or skis. Ruts can be formed by wear, as from studded snow tires common in cold climate areas, or they can form through the deformation of the asphalt concrete pavement or subbase material...

 at that width, so all later wagon
Wagon
A wagon is a heavy four-wheeled vehicle pulled by draught animals; it was formerly often called a wain, and if low and sideless may be called a dray, trolley or float....

s had to have the same width or else risk having one set of wheel
Wheel
A wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...

s suddenly fall into one deep rut but not the other.

In fact, the origins of the standard gauge considerably pre-date the Roman Empire, and may even pre-date the invention of the wheel. The width of prehistoric vehicles was determined by a number of interacting factors which gave rise to a fairly standard vehicle width of a little under 2 m (6.6 ft). These factors have changed little over the millennia, and are still reflected in today's motor vehicles. Road rutting
Rut (roads)
A rut is a depression or groove worn into a road or path by the travel of wheels or skis. Ruts can be formed by wear, as from studded snow tires common in cold climate areas, or they can form through the deformation of the asphalt concrete pavement or subbase material...

 was common in early roads
History of road transport
The history of road transport started with the development of tracks by humans and their beasts of burden.- Early roads :The first forms of road transport were horses, oxen or even humans carrying goods over tracks that often followed game trails, such as the Natchez Trace. In the Stone Age humans...

, even with stone pavements. The initial impetus for the ruts probably came from the grooves made by sled
Sled
A sled, sledge, or sleigh is a land vehicle with a smooth underside or possessing a separate body supported by two or more smooth, relatively narrow, longitudinal runners that travels by sliding across a surface. Most sleds are used on surfaces with low friction, such as snow or ice. In some cases,...

s and slide cars dragged over the surfaces of ancient trackway
Ancient trackway
Ancient trackway can refer to any track or trail whose origin is lost in antiquity. Such paths existed from the earliest prehistoric times and in every inhabited part of the globe...

s. Since early cart
Cart
A cart is a vehicle designed for transport, using two wheels and normally pulled by one or a pair of draught animals. A handcart is pulled or pushed by one or more people...

s had no steering and no brakes, negotiating hills and curves was dangerous, and cutting ruts into the stone helped them negotiate the hazardous parts of the roads.

Neolithic
Neolithic
The Neolithic Age, Era, or Period, or New Stone Age, was a period in the development of human technology, beginning about 9500 BC in some parts of the Middle East, and later in other parts of the world. It is traditionally considered as the last part of the Stone Age...

 wheeled carts found in Europe had gauges varying from 1.3 metre. By the Bronze age
Bronze Age
The Bronze Age is a period characterized by the use of copper and its alloy bronze as the chief hard materials in the manufacture of some implements and weapons. Chronologically, it stands between the Stone Age and Iron Age...

, wheel gauges
Axle track
The axle track in automobiles and other wheeled vehicles which have two or more wheels on an axle, is the distance between the centreline of two roadwheels on the same axle, each on the other side of the vehicle...

 appeared to have stabilized between 1.4 metre which was attributed to a tradition in ancient technology
Ancient technology
During the growth of the ancient civilizations, ancient technology was the result from advances in engineering in ancient times. These advances in the history of technology stimulated societies to adopt new ways of living and governance....

 which was perpetuated throughout European history. The ancient Assyrians, Babylonia
Babylonia
Babylonia was an ancient cultural region in central-southern Mesopotamia , with Babylon as its capital. Babylonia emerged as a major power when Hammurabi Babylonia was an ancient cultural region in central-southern Mesopotamia (present-day Iraq), with Babylon as its capital. Babylonia emerged as...

ns, Persians and Greeks constructed roads with artificial wheelruts cut in rock spaced the wheelspan of an ordinary carriage. Such ancient stone rutways connected major cities with sacred sites, such as Athens
History of Athens
Athens is one of the oldest named cities in the world, having been continuously inhabited for at least 7000 years. Situated in southern Europe, Athens became the leading city of Ancient Greece in the first millennium BCE and its cultural achievements during the 5th century BCE laid the foundations...

 to Eleusis
Eleusinian Mysteries
The Eleusinian Mysteries were initiation ceremonies held every year for the cult of Demeter and Persephone based at Eleusis in ancient Greece. Of all the mysteries celebrated in ancient times, these were held to be the ones of greatest importance...

, Sparta
History of Sparta
The History of Sparta describes the destiny of the ancient Dorian Greek state known as Sparta from its beginning in the legendary period to its forced incorporation into the Achaean League under the late Roman Republic, its conquerors, in 146 BCE, a period of roughly 1000 years...

 to Ayklia, or Elis
Elis
Elis, or Eleia is an ancient district that corresponds with the modern Elis peripheral unit...

 to Olympia
Olympia, Greece
Olympia , a sanctuary of ancient Greece in Elis, is known for having been the site of the Olympic Games in classical times, comparable in importance to the Pythian Games held in Delphi. Both games were held every Olympiad , the Olympic Games dating back possibly further than 776 BC...

. The gauge of these stone grooves was 1.38 metre. The largest number of preserved stone trackways, over 150, are found on Malta.

Some of these ancient stone rutways were very ambitious. Around 600 BC the citizens of ancient Corinth
Ancient Corinth
Corinth, or Korinth was a city-state on the Isthmus of Corinth, the narrow stretch of land that joins the Peloponnesus to the mainland of Greece, roughly halfway between Athens and Sparta. The modern town of Corinth is located approximately northeast of the ancient ruins...

 constructed the Diolkos
Diolkos
The Diolkos was a paved trackway near Corinth in Ancient Greece which enabled boats to be moved overland across the Isthmus of Corinth. The shortcut allowed ancient vessels to avoid the dangerous circumnavigation of the Peloponnese peninsula...

, which some consider the world's first railway, a hard poros limestone road with grooved tracks along which large wooden flatbed cars carrying ships and their cargo were pulled by slaves or draft animals. The grooves were at 1.67 metre centres.

The Roman Empire
Roman Empire
The Roman Empire was the post-Republican period of the ancient Roman civilization, characterised by an autocratic form of government and large territorial holdings in Europe and around the Mediterranean....

 actually made less use of stone trackways than the prior Greek civilization because the Roman roads were much better than those of previous civilizations. However, there is evidence that the Romans used a more or less consistent wheel gauge adopted from the Greeks throughout Europe, and brought it to England with the Roman conquest of Britain
Roman conquest of Britain
The Roman conquest of Britain was a gradual process, beginning effectively in AD 43 under Emperor Claudius, whose general Aulus Plautius served as first governor of Britannia. Great Britain had already frequently been the target of invasions, planned and actual, by forces of the Roman Republic and...

 in AD 43. After the Roman departure from Britain, this more-or-less standard gauge continued in use, so the wheel gauge of animal drawn vehicles in 19th century Britain was 1.4 metre. In 1814 George Stephenson
George Stephenson
George Stephenson was an English civil engineer and mechanical engineer who built the first public railway line in the world to use steam locomotives...

 copied the gauge of British coal wagons in his area (about 1.42 metre) for his new locomotive
Locomotive
A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...

, and for technical reasons widened it slightly to achieve the modern railway standard gauge of 4 foot.

Standard gauge

What became the standard gauge of was chosen for the first main-line railway, the Liverpool and Manchester Railway
Liverpool and Manchester Railway
The Liverpool and Manchester Railway was the world's first inter-city passenger railway in which all the trains were timetabled and were hauled for most of the distance solely by steam locomotives. The line opened on 15 September 1830 and ran between the cities of Liverpool and Manchester in North...

 (L&MR), by the British engineer George Stephenson
George Stephenson
George Stephenson was an English civil engineer and mechanical engineer who built the first public railway line in the world to use steam locomotives...

; the de facto standard for the colliery railways where Stephenson had worked was . Whatever the origin of the gauge, it seemed to be a satisfactory choice: not too narrow and not too wide.

Isambard Kingdom Brunel
Isambard Kingdom Brunel
Isambard Kingdom Brunel, FRS , was a British civil engineer who built bridges and dockyards including the construction of the first major British railway, the Great Western Railway; a series of steamships, including the first propeller-driven transatlantic steamship; and numerous important bridges...

, engineer of the Great Western Railway
Great Western Railway
The Great Western Railway was a British railway company that linked London with the south-west and west of England and most of Wales. It was founded in 1833, received its enabling Act of Parliament in 1835 and ran its first trains in 1838...

, chose the broader gauge of because it offered greater stability and capacity at high speed. Brunel's first locomotives were exactly 7 foot gauge and had no slack, hence the extra quarter inch. The Eastern Counties Railway
Eastern Counties Railway
The Eastern Counties Railway was an early English railway company incorporated in 1836. It was intended to link London with Ipswich via Colchester, and then on to Norwich and Yarmouth. Construction began in late March 1837 on the first nine miles, at the London end of the line.Construction was...

 chose gauge, but soon realised that lack of compatibility was a mistake and changed to Stephenson's gauge. The conflict between Brunel and Stephenson is often referred to as the Gauge War. Several non-interconnecting lines in Scotland were but were changed to standard gauge for compatibility reasons.

In 1845 a British Royal Commission
Royal Commission
In Commonwealth realms and other monarchies a Royal Commission is a major ad-hoc formal public inquiry into a defined issue. They have been held in various countries such as the United Kingdom, Australia, Canada, New Zealand, and Saudi Arabia...

 recommended adoption of as standard gauge in Great Britain, in Ireland. The following year the Parliament of the United Kingdom
Parliament of the United Kingdom
The Parliament of the United Kingdom of Great Britain and Northern Ireland is the supreme legislative body in the United Kingdom, British Crown dependencies and British overseas territories, located in London...

 passed the Gauge Act
Railway Regulation (Gauge) Act 1846
The Railway Regulation Act 1846 introduced mandated standard gauges of for Great Britain, and for Ireland. This signalled the end for Brunel's broad gauge network.-See also:* The GWR "gauge war"* Rail gauge in Ireland* Standard gauge...

, which required that new railways use the standard gauge. Except for the Great Western Railway's broad gauge, few main-line railways in Great Britain used a different gauge. The last Great Western line was converted to standard gauge in 1892.

Broad gauge

Broad gauge refers to any gauge wider than standard gauge
Standard gauge
The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

 or . Russian
Russian gauge
In railway terminology, Russian gauge refers to railway track with a gauge between 1,520 mm and . In a narrow sense as defined by Russian Railways it refers to gauge....

, Indian
Indian gauge
Indian gauge is a track gauge commonly used in India, Pakistan, Bangladesh, Sri Lanka, Argentina and Chile. It is also the gauge that is used on BART , in northern California.- Scotland :...

, Irish
Irish gauge
Irish gauge railways use a track gauge of . It is used in* Ireland * Australia where it is also known as Victorian Broad Gauge* Brazil where it is also known as Bitola larga no Brasil....

, and Iberian
Iberian gauge
Iberian gauge is the name given to the track gauge most extensively used by the railways of Spain and Portugal: namely ....

 gauges are all broad gauges. Broad gauge railways are also common for cranes in docks for short distances. Broad gauge is used to provide better stability or to prevent the easy transfer of rolling stock
Rolling stock
Rolling stock comprises all the vehicles that move on a railway. It usually includes both powered and unpowered vehicles, for example locomotives, railroad cars, coaches and wagons...

 from railroads of other countries for political or military reasons.

Narrow gauge

In many areas narrow gauge railways have been built. As the gauge of a railway is reduced the costs of construction can also be reduced since narrow gauges allow a smaller radius curves allowing obstacles to be avoided rather than having to be built over or through (valleys and hills); the reduced cost is particularly noticeable in mountainous regions. For example, many narrow gauge railways were built in Wales
Wales
Wales is a country that is part of the United Kingdom and the island of Great Britain, bordered by England to its east and the Atlantic Ocean and Irish Sea to its west. It has a population of three million, and a total area of 20,779 km²...

 and the Rocky Mountains
Rocky Mountains
The Rocky Mountains are a major mountain range in western North America. The Rocky Mountains stretch more than from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States...

 of North America. The disadvantage of tight turns and steep gradients is a reduced line speed and smaller trains leading to higher operating costs. Many narrow gauge railways have been abandoned or converted
Gauge conversion
In rail transport, gauge conversion is the process of converting a railway from one rail gauge to another, through the alteration of the railway tracks...

 to standard gauge. Industrial railway
Industrial railway
An industrial railway is a type of railway that is not available for public transportation and is used exclusively to serve a particular industrial, logistics or military site...

s are often constructed using narrow gauge. Sugar cane and banana plantations are often served by narrow gauges such as , as there is little through-traffic to other systems.

The most widely used narrow gauges are Cape gauge
Cape gauge
Cape gauge is a track gauge of between the inside of the rail heads and is classified as narrow gauge. It has installations of around .The gauge was first used by Norwegian engineer Carl Abraham Pihl and the first line was opened in 1862.- Nomenclature :...

 (e.g. Southern and Central Africa, Indonesia, Japan, Taiwan, Philippines, parts of Australia, New Zealand, Honduras and Costa Rica.) metre gauge
Metre gauge
Metre gauge refers to narrow gauge railways and tramways with a track gauge of . In some African, American and Asian countries it is the main gauge. In Europe it has been used for local railways in France, Germany, and Belgium, most of which were closed down in mid 20th century. Only in Switzerland...

 (e.g. SE Asia, 17000 km (10,563.3 mi) in India, but gauge conversion
Gauge conversion
In rail transport, gauge conversion is the process of converting a railway from one rail gauge to another, through the alteration of the railway tracks...

 with Project Unigauge
Project Unigauge
Project Unigauge is an ongoing exercise by Indian Railways to standardise most of the rail gauges in India at 1676 mm broad gauge....

, East Africa, South America) (e.g in Sri Lanka
Sri Lanka Railways
Sri Lanka Railway Department, branded "Sri Lanka Railways", is a key department of the Sri Lankan Government under the Ministry of Transport with a history that begins in 1858...

 Kelani Velley and Udapussellawa lines. All of this gauge tracks were converted into )

There are also minimum gauge railway
Minimum gauge railway
Minimum gauge railways have a gauge of less than or , most commonly , , or . The notion of minimum gauge railways was originally developed by estate railways and by the French company of Decauville for industrial railways....

s.

Break of gauge

When a railway line of one gauge meets a line of another gauge there is a break of gauge. A break of gauge adds cost and inconvenience to traffic that passes from one system to another.

An example of this is on the Transmongolian Railway, where Russia and Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...

 use broad gauge
Broad gauge
Broad-gauge railways use a track gauge greater than the standard gauge of .- List :For list see: List of broad gauges, by gauge and country- History :...

 while China uses standard gauge. At the border, each carriage has to be lifted in turn to have its bogie
Bogie
A bogie is a wheeled wagon or trolley. In mechanics terms, a bogie is a chassis or framework carrying wheels, attached to a vehicle. It can be fixed in place, as on a cargo truck, mounted on a swivel, as on a railway carriage/car or locomotive, or sprung as in the suspension of a caterpillar...

s changed. The whole operation, combined with passport
Passport
A passport is a document, issued by a national government, which certifies, for the purpose of international travel, the identity and nationality of its holder. The elements of identity are name, date of birth, sex, and place of birth....

 and customs
Customs
Customs is an authority or agency in a country responsible for collecting and safeguarding customs duties and for controlling the flow of goods including animals, transports, personal effects and hazardous items in and out of a country...

 control, can take several hours.

Other examples include crossings into or out of the former Soviet Union: Ukraine/Slovakia border on the Bratislava-L'viv train, and from the Romania/Moldova border on the Chişinău-Bucharest train.

This can be avoided however by implementing a system similar to that used in Australia, where some lines between states using different gauges were converted to dual gauge
Dual gauge
A dual-gauge or mixed-gauge railway has railway track that allows trains of different gauges to use the same track. Generally, a dual-gauge railway consists of three rails, rather than the standard two rails. The two outer rails give the wider gauge, while one of the outer rails and the inner rail...

 with three rails, one set of two forming a standard gauge line, with the third rail either inside or outside the standard set forming rails at either narrow or broad gauge. As a result, trains built to either gauge can use the line. However gauges must differ a minimum of twice the width of a rail to allow such a system.

Dual gauge

Dual gauge allows trains of different gauges to share the same track. This can save considerable expense compared to using separate tracks for each gauge, but introduces complexities in track maintenance and signalling, as well as requiring speed restrictions for some trains. If the difference between the two gauges is large enough, for example between and , three-rail dual-gauge is possible, but if the difference is not large enough, for example between and , four-rail dual-gauge is used. Dual-gauge rail lines are used in the railway networks of Switzerland, Australia, Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

, Brazil, North Korea
North Korea
The Democratic People’s Republic of Korea , , is a country in East Asia, occupying the northern half of the Korean Peninsula. Its capital and largest city is Pyongyang. The Korean Demilitarized Zone serves as the buffer zone between North Korea and South Korea...

, Spain, Tunisia
Tunisia
Tunisia , officially the Tunisian RepublicThe long name of Tunisia in other languages used in the country is: , is the northernmost country in Africa. It is a Maghreb country and is bordered by Algeria to the west, Libya to the southeast, and the Mediterranean Sea to the north and east. Its area...

 and Vietnam
Vietnam
Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...

.

When a third rail was proposed to allow dual gauge between Irish gauge
Irish gauge
Irish gauge railways use a track gauge of . It is used in* Ireland * Australia where it is also known as Victorian Broad Gauge* Brazil where it is also known as Bitola larga no Brasil....

 and Standard gauge
Standard gauge
The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

 in Australia, the gauge difference of 6.5 inches was considered too small to allow the third rail to operate safely.

Variable gauge axles

Variable gauge axles (VGA), developed by the Talgo
Talgo
Talgo is a Spanish manufacturer of railway vehicles. It is best known for a design of articulated railway passenger cars in which the wheels are mounted in pairs, but not joined by an axle, and being between rather than underneath the individual coaches...

 company and Construcciones y Auxiliar de Ferrocarriles
Construcciones y Auxiliar de Ferrocarriles
Construcciones y Auxiliar de Ferrocarriles is a rail equipment manufacturer based in Beasain in the Basque Country, Spain. Equipment manufactured by CAF includes light rail vehicles, rapid transit trains, railroad cars and locomotives, as well as variable gauge axles that can be fitted on any...

  (CAF) of Spain, amongst others, enable trains to change gauge with only a few minutes spent in the gauge conversion process. The same system is also used between China and Central Asia, and Poland and Ukraine (SUW 2000
SUW 2000
SUW 2000 is a type of variable gauge system that allows a train to travel across a railway break-of-gauge.The SUW 2000 design is manufactured by Polish company ZNTK Poznań for Polish State Railways...

 and INTERGAUGE variable axles system). China and Poland are standard gauge, while Central Asia and Russia are gauge.

Designed for conversion

Equipment can be designed for easy conversion, such as the Garratt locomotives on the Kenya and Uganda Railway designed for conversion from to . Several classes of steam locomotives of the Victorian Railways
Victorian Railways
The Victorian Railways operated railways in the Australian state of Victoria from 1859 to 1983. The first railways in Victoria were private companies, but when these companies failed or defaulted, the Victorian Railways was established to take over their operations...

 were designed for easy conversion from to . Only one, R766, a preserved historic locomotive, has actually been converted.

Future

Further standardisation of rail gauges seems likely, as individual countries seek to build inter-operable national networks, and international organisations seek to build macro-regional and continental networks. National projects include the Australian and Indian efforts mentioned above to create a uniform gauge in their national networks. The European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...

 has set out to develop inter-operable freight and passenger rail networks across the EU area, and is seeking to standardise track gauge, signalling and electrical power systems. EU funds have been dedicated to assist Baltic states of Lithuania
Lithuania
Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...

, Latvia
Latvia
Latvia , officially the Republic of Latvia , is a country in the Baltic region of Northern Europe. It is bordered to the north by Estonia , to the south by Lithuania , to the east by the Russian Federation , to the southeast by Belarus and shares maritime borders to the west with Sweden...

, and Estonia
Estonia
Estonia , officially the Republic of Estonia , is a state in the Baltic region of Northern Europe. It is bordered to the north by the Gulf of Finland, to the west by the Baltic Sea, to the south by Latvia , and to the east by Lake Peipsi and the Russian Federation . Across the Baltic Sea lies...

 in the construction of some key railway lines (Rail Baltica
Rail Baltica
thumb|300px|Map of Rail Baltica...

) in the standard gauge instead of their gauge, and to assist Spain and Portugal in the construction of high-speed rail
High-speed rail
High-speed rail is a type of passenger rail transport that operates significantly faster than the normal speed of rail traffic. Specific definitions by the European Union include for upgraded track and or faster for new track, whilst in the United States, the U.S...

 lines to connect Iberian cities to one another and to the French high-speed lines. The EU has developed plans for improved freight rail links between Spain, Portugal, and the rest of Europe.

High speed

Except in Russia
High-speed rail in Russia
High-speed rail is emerging in Russia as an increasingly popular means of transport, although the development of such rails is moving at a slower pace than in Western Europe.-Experimental trainsets built in 1974:...

 and Finland, all high-speed rail systems use standard gauge, even in countries like Japan, Taiwan, Spain and Portugal where most of the existing rail lines use a different gauge. Once standard gauge high-speed networks exist, they may provide the impetus for gauge conversion of existing passenger lines to allow for interoperability.

Mining

Heavy duty mining railways which have little interconnection with other lines, such as in the Pilbara region of Western Australia
Western Australia
Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

, also tend to choose standard gauge to allow them to use off-the-shelf equipment, especially heavy-duty rolling stock.

New lines

The United Nations
United Nations
The United Nations is an international organization whose stated aims are facilitating cooperation in international law, international security, economic development, social progress, human rights, and achievement of world peace...

 Economic and Social Commission for Asia and the Pacific (UNESCAP) is planning a Trans-Asian Railway
Trans-Asian Railway
The Trans-Asian Railway is a project to create an integrated freight railway network across Europe and Asia. The TAR is a project of the United Nations Economic and Social Commission for Asia and the Pacific .- Overview :...

 that will link Europe and the Pacific, with a Northern Corridor from Europe to the Korean Peninsula, a Southern Corridor from Europe to Southeast Asia, and a North-South corridor from Northern Europe to the Persian Gulf. All the proposed corridors would encounter one or more breaks of gauge as they cross Asia. Current plans have mechanized facilities at the breaks of gauge to move shipping containers from train to train rather than widespread gauge conversion.
  • Rail lines for iron ore to Oakajee port in Western Australia
    Western Australia
    Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bounded by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east...

     are proposed to form a combined dual gauge network.
  • Rail lines for iron ore to Kribi
    Kribi
    -Location:The coastal town of Kribi lies on the Gulf of Guinea, in Océan Department, South Province, at the mouth of the Kienké River. This location, lies approximately , by road, south of Douala, the loargest city in Cameroon and the busiest seaport in the country...

     in Cameroon
    Transport in Cameroon
    - Railways :Railways in Cameroon are operated by Camrail, a subsidiary of French investment group Bolloré. As of 2008, the country had an estimated 987 km of gauge track....

     are likely to be 1435 mm with a likely connection to the same port from the 1000 mm gauge Cameroon system. This line owned by Sundance Resources may be shared with Legend Mining.

Kenya-Uganda-Sudan proposal

A proposal was aired in October 2004
to build a high-speed electrified line to connect Kenya
Transport in Kenya
Transport in Kenya compares well with other East African countries. Kenya has an extensive network of paved and unpaved roads. Its railway system links the nation's ports and major cities and connects Kenya with neighbouring Uganda...

 with southern Sudan
Transport in Sudan
Transport in Sudan during the early 1990s included an extensive railroad system that served the more important populated areas except in the far south, a meager road network , a natural inland waterway—the Nile River and its tributaries—and a national airline that provided both...

. Kenya and Uganda
Uganda
Uganda , officially the Republic of Uganda, is a landlocked country in East Africa. Uganda is also known as the "Pearl of Africa". It is bordered on the east by Kenya, on the north by South Sudan, on the west by the Democratic Republic of the Congo, on the southwest by Rwanda, and on the south by...

 use gauge, while Sudan uses gauge. Standard gauge
Standard gauge
The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

 was proposed for the project.

Latin America

  • 2008: Proposed link between Venezuela and Colombia
    Rail transport in Colombia
    The Colombia railway network has a total length of 3,304 km. There are 150 km of standard gauge connecting Cerrejón coal mines to maritime port of Puerto Bolivar at Bahia de Portete, and 3,154 km of narrow gauge of which 2,611 km are in use...

  • 2008: Venezuela via Brazil to Argentina - standard gauge
    Standard gauge
    The standard gauge is a widely-used track gauge . Approximately 60% of the world's existing railway lines are built to this gauge...

  • 2008: A proposed metre gauge
    Metre gauge
    Metre gauge refers to narrow gauge railways and tramways with a track gauge of . In some African, American and Asian countries it is the main gauge. In Europe it has been used for local railways in France, Germany, and Belgium, most of which were closed down in mid 20th century. Only in Switzerland...

     line across Southern Paraguay
    Rail transport in Paraguay
    The Rail system in Paraguay consisted primarily of a 376 km main line of standard gauge between Asunción and Encarnación . The infrastructure was administered by Ferrocarriles del Paraguay S.A. , corporation established in 2002...

     to link the Argentine rail at Resistencia
    Resistencia, Chaco
    Resistencia is the capital and largest city in the province of Chaco, in northeastern Argentina. At the 2001 census, the population of the Resistencia city proper was 274,490 inhabitants. It is the anchor of a slightly larger metropolitan area, Greater Resistencia, which comprises three more...

     to the Brazilian line at Cascavel
    Cascavel
    Cascavel is a city and municipality in western Paraná state, Brazil. The population is 296.975 inhabitants.The city is on a plateau 781 meters above sea level...

    ; both those lines are metre gauge, and the new line would allow uninterrupted "bioceanic" running from one coast to the other, from the Atlantic port of Paranaguá
    Paranaguá
    Paranaguá is a city in the state of Paraná in Brazil. Founded in 1648, it is Paraná's oldest city.It is known for its excellent port facilities, being the sea port for Curitiba, the capital of Paraná....

     in Brazil
    Rail transport in Brazil
    Rail transport in Brazil began in the 19th century and there were many different railway companies. The railways were nationalised under RFFSA in 1957...

     to that of Antofagasta
    Antofagasta
    Antofagasta is a port city in northern Chile, about north of Santiago. It is the capital of Antofagasta Province and Antofagasta Region. According to the 2002 census, the city has a population of 296,905...

     in Chile on the Pacific.

See also

  • List of rail gauges
  • Loading gauge
    Loading gauge
    A loading gauge defines the maximum height and width for railway vehicles and their loads to ensure safe passage through bridges, tunnels and other structures...

  • Structure gauge
    Structure gauge
    The structure gauge, also called the minimum clearance outline, is the minimum height and width of tunnels and bridges as well as the minimum height and width of the doors that allow a rail siding access into a warehouse...

  • Rail terminology
    Rail terminology
    Rail terminology is a form of technical terminology. The difference between the American term railroad and the international term railway is the most obvious difference in rail terminology...

  • Longest trains
    Longest trains
    Conventional freight trains can average nearly 2,000 metres. Freight trains with a total length of three or four times that average are possible with the advent of DPUs , or additional locomotive engines between or behind long chains of freight cars...

  • Rail transport by country
    Rail transport by country
    This page provides an index of articles on Rail transport by country.Other indexes available include:*List of railway companies by country*List of countries by rail transport network size*Rail usage statistics by country...

  • History of rail transport by country
  • Breitspurbahn
    Breitspurbahn
    The Breitspurbahn was a planned broad-gauge railway, a personal pet project of Adolf Hitler during the Third Reich of Germany, supposed to run on 3 metre gauge track with double-deck coaches between major cities of Grossdeutschland, Hitler's expanded Germany.-History:Since reparations due after...

  • Gauge conversion
    Gauge conversion
    In rail transport, gauge conversion is the process of converting a railway from one rail gauge to another, through the alteration of the railway tracks...

  • Heaviest trains
    Heaviest trains
    The heaviest trains in the world are freight trains hauling bulk commodities such as coal and iron ore. One might distinguish between regular operations, and occasional record breaking runs...

  • Minimum railway curve radius
    Minimum railway curve radius
    The minimum railway curve radius, the shortest design radius, has an important bearing on constructions costs and operating costs and, in combination with superelevation in the case of train tracks, determines the maximum safe speed of a curve. Superelevation is not a factor on tramway tracks...

  • Third rail
    Third rail
    A third rail is a method of providing electric power to a railway train, through a semi-continuous rigid conductor placed alongside or between the rails of a railway track. It is used typically in a mass transit or rapid transit system, which has alignments in its own corridors, fully or almost...

  • Rail transport modelling scales
    Rail transport modelling scales
    Rail transport modelling utilises a variety of scales to ensure scale models look correct when placed next to each other. Model railway scales are standardized worldwide by many organizations and hobbyist groups...

  • Model railway scales

  • External links

    The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
     
    x
    OK