Londonderry, city, northwestern Northern Ireland, at the head of Lough Foyle, on the northern coast of Northern Ireland. Londonderry is a seaport and has manufactures that include clothing, food products, furniture, and boats. Located here are the Protestant Saint Columba's Cathedral (17th century) and Magee University College (1865). St. Columba established an abbey on the site about AD546, around which the community of Derry grew. In 1613 jurisidiction of the town was granted to London, and it was renamed Londonderry. During the Glorious Revolution (1688-89), the city withstood a siege by the forces of James II for 105 days. Beginning in 1969, bitter fighting broke out here between Roman Catholic and Protestant factions. Before 1974 Londonderry was the county town of the former county of Londonderry. Population (1991) 72,334.
