County of Londonderry

A maritime county in the north of Ulster bounded, on the north, by the Atlantic Ocean; on the east, by County Antrim; on the south, by County Tyrone; and on the west, by Lough Neagh, Lough Beg, the Lower (river) Bann, and County Donegal.

The river Ballinderry traces the southern boundary over the last five miles of its run to Lough Neagh.

A lofty line of watershed along the central summits of the great mountainous district of northern Ulster forms most of the boundary westward from the vale of the river Ballinderry to Foyle Valley.

An artificial line of about eight miles in extent winds round a district on the west side of the River Foyle, down to the beginning of that river's expansion into estuary; and Lough Foyle forms the whole of the western boundary thence to the ocean.

The district east of the River Bann extends at Coleraine; and the district west of the River Foyle, that of Derry; so that, but for the artificial disposition of territory connected with these two towns, the Bann and the Foyle would have formed boundary-lines over the entire extent of their contact with the county, and rendered it a naturally well-defined region, from river to river, and from the line of watershed to the ocean.

The outline of the county is roughly triangular, with its sides facing the east, the south-west and the north-west.

Its area comprises almost 520,000 acres.

The highest mountaain is Sawel Mountain (The Sperrins), at 2,224 feet.