District (pop., 2001: 37,659), northeastern Northern Ireland.
Established in 1974, it lies on Belfast Lough. The name, meaning "rock of Fergus," commemorates King Fergus, shipwrecked off the coast с AD 320. Carrickfergus town (pop., 1991: 22,786) is the district seat. Carrickfergus Castle, a relic of the Norman period, sits on a crag above the town; it was a refuge for the Protestants of Antrim in the English Civil Wars .