Zelenogorsk (Saint Petersburg)

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Zelenogorsk (Russian: Зеленого́рск), known as Terijoki prior to 1948 (a name still used in Finnish and Swedish), is a municipal town in Kurortny District of the federal city of St. Petersburg, Russia, located in part of the Karelian Isthmus on the shore of the Gulf of Finland. Population: 14,958 (2010 Census). It has a station on the St. Petersburg-Vyborg railroad. It is located about 50 kilometers (31 mi) northwest of central Saint Petersburg.

The first mention of Terijoki in documents dates back to 1548, when Antti from Terijoki was among several state smugglers by the order of the Swedish king Gustav Vasa in Vyborg. In the first half of the 17th century, there were 29 households in Terijoki.

After the Finnish War until 1917, Terijoki was part of the Grand-Duchy of Finland, ruled by the Grand Dukes of Finland, who were the Tsars of Russia, (1812–1917). Even though all of Finland was part of the Russian Empire, a customs border was in Terijoki. A valid Passport was needed for crossing the border between Russia and the Grand Duchy of Finland. Vladimir Lenin managed to travel over the border in secrecy to Finland in 1907. Later on 3 April 1917, he returned through the Terijoki border control disguised as a heater of a Finnish Railways - Finlyandsky Rail Terminal locomotive. When the Republic of Finland was established on 6 December 1917, Terijoki became a part of it, and remained so until it was occupied by the Soviet Union in the Winter War. It was regained by Finland in 1941, in the Continuation War, but then was occupied again by the Red Army and anexed to the Soviet Union again in 1944.