Birr Barracks (Irish: Dún Bhiorra) also known as Crinkill Barracks (Irish: Dún Chríonchoill) was a military installation in Crinkill, near Birr, County Offaly in Ireland.

The barracks were built by Bernard Mullins at the instigation of Lawrence Parsons, 2nd Earl of Rosse, who had supported the need to build some barracks within a few hours’ march of the River Shannon, and were completed between 1809 and 1812.

[1] In 1873 a system of recruiting areas based on counties was instituted under the Cardwell Reforms and the barracks became the depot for the 100th (Prince of Wales's Royal Canadian) Regiment of Foot and the 109th Regiment of Foot (Bombay Infantry).

[1] Some 6,000 recruits enlisted at the barracks during the First World War: an airfield was built there in 1917 and Sergeant John Allan was killed when his plane crashed into Crinkill House on 28 March 1919.

[1] The Prince of Wales's Leinster Regiment (Royal Canadians) was disbanded at the time of Irish Independence in 1922.