Kilmainham Gaol is one of the largest unoccupied Gaols in Europe, which was built in 1787 and opened in 1796 as the new County Gaol for Dublin.

It closed its doors in 1924 and now it is a museum run by Office of Public Works.  Many Irish revolutionaries, including the leaders of the 1916 Easter Rising, were imprisoned and executed in the prison by the British. Attractions include a major exhibition detailing the political and penal history of the prison and its restoration.