Vyborg (in; in; in) is a Russian city of: 78700 inhabitants (2004) of the Oblast of Leningrad, located on the Isthmus of Karelia, which was until the beginning of the Second world war a town of Finland. Its annexation by the the USSR was ratified at the time of the peace treaty of Moscow of 1940 which put an end to the Guerre of Winter which opposed the two countries during the winter 1939 - 1940.

Vyborg has a port specialized in the traffic of bulk with a traffic of 2 million tons per annum (2005).

It is the birthplace of Martti Ahtisaari.

The library of the city is one of the major achievements of the Finnish architect Alvar Aalto.