"Twenty One Years" is an Irish traditional song by Dermot Hegarty and the Plainsmen.

[1] The singer describes a prison sentence of twenty-one years in HM Prison Dartmoor, and complains that his lover does not write.

[2] "Twenty One Years" was released in April 1970.

[3] It was number 1 on the Irish Singles Chart for five weeks in 1970.

[4]