Londonderry, a maritime county of Ulster, 40 miles long by 34 broad, is bounded N. by the Atlantic, and elsewhere by Antrim, Lough Neagh, Tyrone, and Donegal. Area, 816 sq. m. Pop. (1841) 222,174; (1901) 144,404, of whom 65,296 were Catholics, 45,682 Presbyterians, and 27,804 Episcopalians. The surface rises inland, Mount Sawell, on the southern border, being 2236 feet high. The coast-line (30 miles long) is generally bold and precipitous; but the shore of Lough Foyle is in most places an unvarying plain, large tracts having been reclaimed. The river Bann from Lough Neagh forms part of the eastern border; the river Foyle intersects the western extremity. Thirty-seven per cent. of the area is permanent grass, and much of the cultivated soil is meadow land and clover. Linen is the staple manufacture. The county returns two members, and the county town, Londonderry, one. The other towns are Coleraine and Limavady.
Londonderry, or Derry, the county town, is Bituated on an eminence overlooking the river Foyle, 3 miles from its mouth and 18 from the entrance to Lough Foyle, by rail 163 miles NNW. of Dublin and 95 NW. of Belfast. Pop. (1851) 19,888 ; (1881) 29,162 ; (1901) 39,892. Londonderry grew up round a monastery founded in 546 by St Coluinba. It formed part of the escheated territory granted in 1613 to the London companies, and under their management rose to importance, and was strongly fortified. In the Irish war of the Revolution thirteen Londonderry apprentices closed its gates against James II. ; and the townsfolk, shouting 'No surrender,' manned the walls. The 105 days' siege that then ensued, from April to August 1689, is one of the most celebrated events in Irish history. The walls still surround a part of the town one mile in circumference, but now the greater part of the city lies outside them. The left bank of the river is connected by an iron bridge, 1200 feet in length, with an extensive suburb called Waterside. The Protestant cathedral dates from 1633 ; it was restored in 1886. A handsome Roman Catholic cathedral, the court-house, guildhall (1890; cost £20,000), harbour-offices, post-office, custom-house, and banks are the other chief buildings. The siege is commemorated by a triumphal arch - one of the gates of the city - erected in 1789, and a column to the Rev. George Walker, who was the soul of the defence. The Presbyterian theological Magee College was founded in 1865. The industrial establishments include linen (shirt-making) factories, distilleries, iron-foundries, flour-mills, and shipbuilding-yards. In Lough Foyle are valuable salmon-fisheries. The harbour is deep, extensive, and safe. The imports include grain, flour, timber, and spirits; the exports are chiefly agricultural produce. Londonderry returns one member. See works by Hempton (1861) and Dwyer (1893).