Dunnideer Castle, now ruined, was a tower house located near Insch, Aberdeenshire, Scotland.
It was built c. 1260 partially from the remains of an existing vitrified hill fort in the same location.
It consisted of a single rectangular tower of 15 m by 12.5 m with walls 1.9 m thick.
Evidence suggests that a first-floor hall existed and that it had several floors.
[1] The tower house is built within an older prehistoric vitrified hillfort dating to c250 BC, excavated by Dr Murray Cook of Rampart Scotland.