seaport and market town of Ireland, county of Donegal, situated on the Erne, at its influx into the bay of Donegal. Lat. 54. 50. N. Long. 8. 11. W. The river is here crossed by a bridge of 14 arches, which connects the town with the suburb of Port. Below the bridge the river forms a beautiful cascade 150 yards wide, with a fall at low-water of 16 feet. The harbour is a small creek of Donegal Bay, about 600 yards long, and 350 yards broad, and is only accessible to small vessels. The town contains a church, several chapels, a bank, market-house, barracks, and a union workhouse. Previous to the Union, Ballyshannon returned two members to the Irish Parliament. Pop. in 1851, 3697.