Wikipedia
Nyckelharpa
A nyckelharpa ("keyed fiddle", or literally "key harp", plural nyckelharpor) is a traditional Swedish musical instrument. It is a string instrument or chordophone. Its keys are attached to tangents which, when a key is depressed, serve as frets to change the pitch of the string.
The nyckelharpa is similar in appearance to a fiddle or the big Sorb geige or viol. Structurally, it is more closely related to the hurdy-gurdy, both employing key-actuated tangents to change the pitch. The nyckelharpa and its tonal range appear on the reverse of the Swedish 50 kronor banknote.