Delfin (Дельфин, Russian: "Dolphin") was the first Russian battle submarine

Submarine

A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...

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She was designed by Naval architect Senior Assistant I.G. Bubnov, Lieutenant M.N. Beklemishev and Lieutenant I.S. Goryunov of the Construction Commission for Submarines (later the Rubin Design Bureau

Rubin Design Bureau

Rubin Central Design Bureau for Marine Engineering in Saint Petersburg is one of the main Russian centers of submarine design, having designed more than two-thirds of all nuclear submarines in the Russian Navy...

), laid down by Baltic plant at St. Petersburg

Saint Petersburg

Saint Petersburg is a city and a federal subject of Russia located on the Neva River at the head of the Gulf of Finland on the Baltic Sea...

, launched in 1902, and entered service in 1903, training officers and sailors.

On 29 June 1904 the submarine sank in the Neva River

Neva River

The Neva is a river in northwestern Russia flowing from Lake Ladoga through the western part of Leningrad Oblast to the Neva Bay of the Gulf of Finland. Despite its modest length , it is the third largest river in Europe in terms of average discharge .The Neva is the only river flowing from Lake...

 by the wall of the Baltic shipyard

Baltic Shipyard

The Baltic Shipyard is one of the oldest shipyards in Russia. It is located in Saint Petersburg in the south-western part of the Vasilievsky Island. It is one of the three shipyards active in Saint Petersburg...

 during a test dive. The captain and 24 crewmen were killed, and 12 men were rescued.

Delfin was salvaged and transferred to the Siberia

Siberia

Siberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...

n flotilla, arriving in Vladivostok

Vladivostok

The city is located in the southern extremity of Muravyov-Amursky Peninsula, which is about 30 km long and approximately 12 km wide.The highest point is Mount Kholodilnik, the height of which is 257 m...

 in late 1904. She served until 1917, seeing action in the Russo-Japanese War

Russo-Japanese War

The Russo-Japanese War was "the first great war of the 20th century." It grew out of rival imperial ambitions of the Russian Empire and Japanese Empire over Manchuria and Korea...

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During World War I Delfin was transferred to Murmansk and served in Northern flotillia. In 1917 she was stricken and scrapped in 1920.

The centenary of Delfin’s sinking - the first Russian submarine accident - was marked by the St. Petersburg Submariners Club with wreath-laying, a mourning service, and by guards of honor and an orchestra marching at the Smolenskoye Orthodox cemetery.