Port of the five seas. High-speed passenger train Siemens Velaro RUS "Sapsan" runs from Moscow to Saint Petersburg at the bridge over the Moscow canal. The Moscow сanal is a canal that connects the Moskva (Moscow) River with the Volga River. Length of the canal is 128 km. It was constructed from the year 1932 to the year 1937 by Gulag prisoners during the early to mid Stalin era. Thanks to the Moscow Canal, Moscow has access to five seas: the White Sea, Baltic Sea, Caspian Sea, Sea of Azov, and the Black Sea. This is why Moscow is sometimes called the "Seaport of the five seas".