Carrickfergus Castle is a Norman castle in Northern Ireland, situated in the town of Carrickfergus in County Antrim, on the shore of Belfast Lough. Besieged in turn by the Scots, Irish, English and French, the castle played an important military role until 1928 and remains one of the best preserved medieval structures in the whole of Ireland. Today it is maintained by the Environment and Heritage Service.

Origins
Carrickfergus Castle was built by John de Courcy in 1177 as his headquarters, after he conquered eastern Ulster in 1177 and ruled as a petty king until 1204, when he was ousted by another Norman adventurer, Hugh de Lacy. Initially de Courcy built the inner ward, a small bailey at the end of the promontory with a high polygonal curtain wall and east gate.

It had a number of buildings, including the great hall. From its strategic position on a rocky promontory, originally almost surrounded by sea, the castle commanded Belfast Lough, and the land approaches into the walled town that developed beneath its shadows.

Later Use
In 1778 one of the first battles of the American War of Independence took place on Belfast Lough just by the castle. John Paul Jones attacked a British navy ship and forced her to strike her colours. In 1797 it became a prison and it was heavily defended during the Napoleonic Wars; six guns on the east battery remain of the twenty-two that were used in 1811.

For a century it remained a magazine and armoury. During the First World War it was used as a garrison and ordnance store and during the Second World War as an air raid shelter.

It was garrisoned continuously for about 750 years until 1928, when its ownership was transferred to the government for preservation as an ancient monument and it is open to the public. The banqueting hall has been fully restored and there are many exhibits to show what life was like in medieval times.

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