The Moscow Canal was originally known as the Moscow-Volga Canal and was constructed between 1932 and 1937 using GULAG prisoner labour. It connects Moscow to the Volga thereby providing the city with water access to the White Sea, the Baltic Sea, the Caspian Sea, the Azov Sea and the Black Sea. For the purposes of the construction, Dmitrovlag, later known as Dmitlag, was established as part of the GULAG system in Dmitrov with its administration located at the Borisoglebsky Monastery. The organisation Memorial states that at its height almost 200,000 prisoners were held at the camp which was closed in 1937 with mass executions taking place.