 Notable historic sites in Cumbria include Carlisle Castle, Furness Abbey, Hardknott Roman Fort, Brough Castle and Hadrian's Wall (also a World Heritage Site).The county of Cumbria was created in April 1974 through an amalgamation of the administrative counties of Cumberland and Westmorland, to which parts of Lancashire (the area known as Lancashire North of the Sands) and the West Riding of Yorkshire were added.During the Neolithic period the area contained an important centre of stone axe production (the so-called 'Langdale Axe Factory'), products of which have been found across Great Britain.