Säkkijärven polkka

Säkkijärven polkka (Finnish pronunciation: [ˈsækːiˌjærʋen ˈpolkːɑ]; "the Säkkijärvi polka") is a well-known folk tune from Finland that is very popular with Finnish accordionists. It was popularized by Viljo "Vili" Vesterinen (1907–1961). The first record of the existence of the tune is from Säkkijärvi (now Kondrat'evo in Leningrad Oblast). Most famous and historical is the recording made on June 17, 1939 with former members of the Dallapé Orchestra. The recording took place in the ballroom of the German school in Helsinki. The recording became the most famous performance of the Säkkijärven polkka.

The tune was famously used in the Continuation War as a countermeasure against mines left by the Soviet army that would have been triggered by a specific chord sequence on a specific communication channel.