Before the Finnish Winter War, Finland had built up a line of defence (Mannerheimlinjen) that crossed the Karelian nose as a defence against the Soviet Union. After the peace of March 1940, this line of defence lay in the Soviet Union and Finland began a new construction of a line of defence under what has been called the middle peace (the time between the Finnish winter war and the continuing war). The line was called the Salpal line and was a 1200 kilometres line of defence that ran from southern to northern Finland. However, the Salpa line was never used during the continuation war because Finland surrendered before the fighting reached the line. The Mannerheim line is today in Russia and there are remains of it but there is no museum on site. However, there are museums among the remnants of the Salpa line that can be visited. One of them is located in Virolahti in south-eastern Finland, just under 200 kilometres east of Helsinki.

Current status: Preserved with museum (2009).

Location: 60°34' 23.82" N 27°35' 38.03" E

Get there: Car.

My comment:

Although there were never any fighting at the Salpa Line, it is interesting to wander around among the well-preserved defenses.

Follow up in books: Trotter, R William: The Russo-Finnish Winter War of 1939-1940 (2010).