Inchtuthil is the site of a Roman legionary fortress situated on a natural platform overlooking the north bank of the River Tay southwest of Blairgowrie, Perth and Kinross, Scotland (Roman Caledonia). It was built in AD 82 or 83 as the advance headquarters for the forces of governor Gnaeus Julius Agricola in his campaign against the Caledonian tribes. Positioned at the head of one of the main routes in and out of the Scottish Highlands, it was occupied by Legion XX Valeria Victrix and covered a total area of 21.5 hectares (53 acres).