Leitrim is a maritime county in north central Ireland in Connaught Province Province, bounded on the north by Donegal Bay, on the northeast by County Fermanagh, on the east by County Cavan, on the southeast by Longford, on the southwest by Roscommon, and on the west by Sligo. The area is 580 square miles.
Leitrim is divided in almost equal parts by Lough Allen, which lies between Drumkeerin and Drumshanbo districts. The truskmore Mountains, with peaks rising above 2000 feet, traverse the northern areas. The Lackagh Hills run through the central and eastern sections, and the Brawlieve Hills extend southeast along the western side of the county. Leitrim has numerous lakes in addition to Lough Allen. The River Shannon enters the county south of Lough Allen. Other smaller rivers are the Owenmore and Bonnet. Carrick-on-Shannon is the county town.
Located within the county are the monastic ruins of Fenagh and Annaduff, and the remains of Castle Breffni, Manor Hamilton, and Castle John.
