Bull Run Mountains
Encyclopedia
The Bull Run Mountains are a mountain range of the Blue Ridge Mountains
in northern Virginia
in the United States
. Located approximately 20 miles (32.2 km) east of the main chain, across the Loudoun Valley
. The Bull Run Mountains, together with Catoctin Mountain
in Virginia and Maryland
, make up the easternmost front of the Blue Ridge.
The range is home to the Bull Run Mountains Conservancy Area, and to residents of the Bull Run Mountain Estates.
Interstate 66
, the John Marshall Highway (Virginia Route 55) and the Manassas Gap Railroad
pass through the range at Thoroughfare Gap
.
in Loudoun County
, through western Prince William County
to New Baltimore
in Fauquier County
. In the north, from Aldie to the headwaters of Bull Run Creek
, the range is entirely within Loudoun County and serves as the eastern border of the southern Loudoun Valley
. South of Bull Run Creek, the watershed of the range forms the western border of Prince William with Fauquier and thus the eastern slopes are in the former county, while the western slopes are in the latter.
The range consists of three closely spaced ridges (with several spurs), which converge in the center of the range. The northern section of the range consists of a solitary ridge, which dies out towards the center of the range, whereupon two ridges to the west gain prominence. In the southern section the central ridge dies out as well and the western-most ridge solely comprises the range. The Broken Hills
intersect the range south of I-66 in the southern section.
interspersed with white quartz
and Precambrian
metamorphosed basalt
flows. The lower ridges on the eastern front also contain Jurassic
basalt flows. These rocks were transported westward to their current location and uplifted during the Alleghenian Orogeny
.
was fought on the mountain prior to the Second Battle of Manassas during the American Civil War
.
Blue Ridge Mountains
The Blue Ridge Mountains are a physiographic province of the larger Appalachian Mountains range. This province consists of northern and southern physiographic regions, which divide near the Roanoke River gap. The mountain range is located in the eastern United States, starting at its southern-most...
in northern Virginia
Virginia
The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...
in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
. Located approximately 20 miles (32.2 km) east of the main chain, across the Loudoun Valley
Loudoun Valley
The Loudoun Valley is a small, but historically significant valley in the Blue Ridge Mountains located in Loudoun County in northwestern Virginia in the United States.-Geography:...
. The Bull Run Mountains, together with Catoctin Mountain
Catoctin Mountain
Catoctin Mountain, along with the geologically associated Bull Run Mountains, comprises the easternmost mountain ridge of the Blue Ridge Mountains, which are in turn a part of the Appalachian Mountains range...
in Virginia and Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, make up the easternmost front of the Blue Ridge.
The range is home to the Bull Run Mountains Conservancy Area, and to residents of the Bull Run Mountain Estates.
Interstate 66
Interstate 66
Interstate 66 is an Interstate Highway in the eastern United States. As indicated by its even route number, it runs in an east–west direction. Its western terminus is at Middletown, Virginia, at an intersection with Interstate 81; its eastern terminus is in Washington, D.C., at an...
, the John Marshall Highway (Virginia Route 55) and the Manassas Gap Railroad
Manassas Gap Railroad
The Manassas Gap Railroad was an historic intrastate railroad in the Southern United States which ran from Mount Jackson, Virginia to the Orange and Alexandria Railroad at a junction called "Manassas Junction", which later became the city of Manassas, Virginia...
pass through the range at Thoroughfare Gap
Thoroughfare Gap (Bull Run Mountain)
Thoroughfare Gap is a water gap in the Bull Run Mountains created by Broad Run between High Point Mountain to the north and Bisquit Mountain to the south...
.
Geography
The range extends in a southwest-northeast orientation for approximately 15 miles (24.1 km) from AldieAldie, Virginia
Aldie is an unincorporated village located on the John Mosby Highway between Gilbert's Corner and Middleburg in Loudoun County, Virginia. It is located in a gap between the Catoctin Mountain and Bull Run Mountain, through which the Little River flows...
in Loudoun County
Loudoun County, Virginia
Loudoun County is a county located in the Commonwealth of Virginia, and is part of the Washington Metropolitan Area. As of the 2010 U.S. Census, the county is estimated to be home to 312,311 people, an 84 percent increase over the 2000 figure of 169,599. That increase makes the county the fourth...
, through western Prince William County
Prince William County, Virginia
-National protected areas:* Featherstone National Wildlife Refuge* Manassas National Battlefield Park* Occoquan Bay National Wildlife Refuge* Prince William Forest Park-Government and politics:...
to New Baltimore
New Baltimore, Virginia
New Baltimore, Virginia is a census-designated place in eastern Fauquier County, Virginia, United States. The population as of the 2010 Census was 8,119. Although the community has existed since the early 19th century, it has had its most significant growth since the 1980s...
in Fauquier County
Fauquier County, Virginia
As of the census of 2000, there were 55,139 people, 19,842 households, and 15,139 families residing in the county. The population density was 85 people per square mile . There were 21,046 housing units at an average density of 32 per square mile...
. In the north, from Aldie to the headwaters of Bull Run Creek
Bull Run (Occoquan River)
Bull Run is a free-flowing tributary stream of the Potomac River that originates from a spring in the Bull Run Mountains in Loudoun County, Virginia, and flows south to the Occoquan River...
, the range is entirely within Loudoun County and serves as the eastern border of the southern Loudoun Valley
Loudoun Valley
The Loudoun Valley is a small, but historically significant valley in the Blue Ridge Mountains located in Loudoun County in northwestern Virginia in the United States.-Geography:...
. South of Bull Run Creek, the watershed of the range forms the western border of Prince William with Fauquier and thus the eastern slopes are in the former county, while the western slopes are in the latter.
The range consists of three closely spaced ridges (with several spurs), which converge in the center of the range. The northern section of the range consists of a solitary ridge, which dies out towards the center of the range, whereupon two ridges to the west gain prominence. In the southern section the central ridge dies out as well and the western-most ridge solely comprises the range. The Broken Hills
Broken Hills (Virginia)
The Broken Hills is a range of low-lying mountains and ridges in northern Fauquier County, Virginia.The range begins just to the west of the southern Bull Run Mountains, north of Warrentown and continues to the eastern edge of Blue Mountain. Interstate 66 and Virginia State Route 55 run just north...
intersect the range south of I-66 in the southern section.
Geology
The Bull Run Mountains are a geological extension of the same formation that makes up the Catoctin Mountain. This formation consist mainly of Catoctin greenstoneGreenschist
Greenschist is a general field petrologic term applied to metamorphic or altered mafic volcanic rock. The term greenstone is sometimes used to refer to greenschist but can refer to other rock types too. The green is due to abundant green chlorite, actinolite and epidote minerals that dominate the...
interspersed with white quartz
Quartz
Quartz is the second-most-abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz,...
and Precambrian
Precambrian
The Precambrian is the name which describes the large span of time in Earth's history before the current Phanerozoic Eon, and is a Supereon divided into several eons of the geologic time scale...
metamorphosed basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...
flows. The lower ridges on the eastern front also contain Jurassic
Jurassic
The Jurassic is a geologic period and system that extends from about Mya to Mya, that is, from the end of the Triassic to the beginning of the Cretaceous. The Jurassic constitutes the middle period of the Mesozoic era, also known as the age of reptiles. The start of the period is marked by...
basalt flows. These rocks were transported westward to their current location and uplifted during the Alleghenian Orogeny
Alleghenian orogeny
The Alleghenian orogeny or Appalachian orogeny is one of the geological mountain-forming events that formed the Appalachian Mountains and Allegheny Mountains. The term and spelling Alleghany orogeny was originally proposed by H.P. Woodward in 1957....
.
History
The Battle of Thoroughfare GapBattle of Thoroughfare Gap
The Battle of Thoroughfare Gap, also known as Chapman's Mill, took place on August 28, 1862, in Fauquier County and Prince William County, Virginia, as part of the Northern Virginia Campaign of the American Civil War. Confederate forces under Maj. Gen. James Longstreet successfully drove back Union...
was fought on the mountain prior to the Second Battle of Manassas during the American Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...
.
Peaks and Gaps
- Peaks (from north to south)
- Aldie Mountain [700 feet (213.4 m)]
- Long Hill Mountain [740 feet (225.6 m)
- Bull Run Ridge [1240 feet (378 m)]
- High Acre Ridge [1320 feet (402.3 m)]
- Griffen Mountain [950 feet (289.6 m)]
- Fishback Ridge [880 feet (268.2 m)]
- Signal Mountain [1369 feet (417.3 m)]
- High Point Mountain [1311 feet (399.6 m)]
- Bisquit Mountain [850 feet (259.1 m)]
- Pond Mountain [840 feet (256 m)]
- Gaps (from north to south)
- Buchannon Gap [587 feet (178.9 m)]
- Cold Spring Gap [702 feet (214 m)]
- Hopewell Gap [860 feet (262.1 m)]
- Thoroughfare Gap [423 feet (128.9 m)]