The Krab (Краб - Crab) was a submarine built for the Imperial Russian Navy

Imperial Russian Navy

The Imperial Russian Navy refers to the Tsarist fleets prior to the February Revolution.-First Romanovs:Under Tsar Mikhail Feodorovich, construction of the first three-masted ship, actually built within Russia, was completed in 1636. It was built in Balakhna by Danish shipbuilders from Holstein...

. She was designed by Mikhail Petrovich Nalyotov as the world's first submarine minelayer

Minelayer

Minelaying is the act of deploying explosive mines. Historically this has been carried out by ships, submarines and aircraft. Additionally, since World War I the term minelayer refers specifically to a naval ship used for deploying naval mines...

, although due to construction delays the German UC submarine

German Type UC I submarine

The Type UC I submarines were a class of small coastal minelaying U-boats built in Germany during the early part of World War I. They were the first operational minelaying submarines in the world . A total of fifteen boats were built...

s entered service earlier. The mines were stowed in two horizontal galleries exiting through the stern. Diving depth was 45 metres. This ship was built by the Naval yard in Nikolayev

Mykolaiv

Mykolaiv , also known as Nikolayev , is a city in southern Ukraine, administrative center of the Mykolaiv Oblast. Mykolaiv is the main ship building center of the Black Sea, and, arguably, the whole Eastern Europe.-Name of city:...

 by the Black Sea

Black Sea

The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...

 (now Mykolaiv

Mykolaiv

Mykolaiv , also known as Nikolayev , is a city in southern Ukraine, administrative center of the Mykolaiv Oblast. Mykolaiv is the main ship building center of the Black Sea, and, arguably, the whole Eastern Europe.-Name of city:...

, Ukraine

Ukraine

Ukraine is a country in Eastern Europe. It has an area of 603,628 km², making it the second largest contiguous country on the European continent, after Russia...

). She was ordered in 1908, launched in September 1912 and entered service in 1915.

Service

This submarine fought during World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

 in the Black Sea Fleet

Black Sea Fleet

The Black Sea Fleet is a large operational-strategic sub-unit of the Russian Navy, operating in the Black Sea and the Mediterranean Sea since the late 18th century. It is based in various harbors of the Black Sea and the Sea of Azov....

. She laid several minefields which accounted for the Turkish gunboat

Gunboat

A gunboat is a naval watercraft designed for the express purpose of carrying one or more guns to bombard coastal targets, as opposed to those military craft designed for naval warfare, or for ferrying troops or supplies.-History:...

 Isa Reis and the Bulgaria

Bulgaria

Bulgaria , officially the Republic of Bulgaria , is a parliamentary democracy within a unitary constitutional republic in Southeast Europe. The country borders Romania to the north, Serbia and Macedonia to the west, Greece and Turkey to the south, as well as the Black Sea to the east...

n torpedo boat

Torpedo boat

A torpedo boat is a relatively small and fast naval vessel designed to carry torpedoes into battle. The first designs rammed enemy ships with explosive spar torpedoes, and later designs launched self-propelled Whitehead torpedoes. They were created to counter battleships and other large, slow and...

 Shumni as well as several merchant ships. After the Russian Revolution of 1917

Russian Revolution of 1917

The Russian Revolution is the collective term for a series of revolutions in Russia in 1917, which destroyed the Tsarist autocracy and led to the creation of the Soviet Union. The Tsar was deposed and replaced by a provisional government in the first revolution of February 1917...

 the boat was captured by the Germans and transferred to the British intervention force

Allied Intervention in the Russian Civil War

The Allied intervention was a multi-national military expedition launched in 1918 during World War I which continued into the Russian Civil War. Its operations included forces from 14 nations and were conducted over a vast territory...

 who scuttled the boat near Sevastopol

Sevastopol

Sevastopol is a city on rights of administrative division of Ukraine, located on the Black Sea coast of the Crimea peninsula. It has a population of 342,451 . Sevastopol is the second largest port in Ukraine, after the Port of Odessa....

 to prevent capture by the Bolsheviks. The wreck was raised in 1935 and scrapped.