Riihimäki-Saint Petersburg railroad

The Riihimäki–Saint Petersburg railway is a 385-kilometre (239 mi) long segment of the Helsinki–Saint Petersburg connection, which is divided between Saint Petersburg and Leningrad Oblast in Russia and the province of Southern Finland in Finland.

It was constructed in 1867–70 (starting from both ends), entirely by the government of the autonomous Grand Duchy of Finland of the Russian Empire, although the short section between Saint Petersburg and Beloostrov (where Russian customs was situated in 1870–1939) was laid in Russia (Saint Petersburg Governorate). The Finlyandsky Rail Terminal was opened in Saint Petersburg in 1870 in order to serve this line.

The rail link starts at the Riihimäki railway station of the Helsinki–Hämeenlinna connection, heading towards the Finlyandsky Railway Terminal of Saint Petersburg through Lahti railway station, Kouvola railway station, Vyborg railway station (formerly Viipuri/Viborg/Wiborg) and Zelenogorsk (formerly Terijoki). Until 1917, when Finland became an independent state, the road had been operated by the Finnish State Railways for all its length, including that section. Due to construction of the southern sections of the railroad, the western part of the Karelian Isthmus on both sides of the Russian-Finnish border became a popular dacha resort place among wealthy St. Petersburgers in the late nineteenth century.

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