Fermoy is a town on the River Blackwater in east County Cork, Ireland. As of the 2022 census, the town and environs had a population of approximately 6,700 people. It is located in the historical barony of Condons and Clangibbon, and is in the Dáil constituency of Cork East.

The Blackwater or Munster Blackwater is a river which flows through counties Kerry, Cork and Waterford in Ireland. It rises in the Mullaghareirk Mountains in County Kerry and then flows in an easterly direction across County Cork through the towns of Mallow and Fermoy. It then enters County Waterford where it flows through Lismore, before abruptly turning south at Cappoquin and finally draining into the Celtic Sea at Youghal Harbour in Cork. In total, the Blackwater is 169 km (105 mi) long.