Muff is a village in County Donegal, Ireland. It is near the mouth of the River Foyle (where it flows into Lough Foyle) and sits at the border between the Republic of Ireland and Northern Ireland. The village of Culmore and the city of Derry are to the south. Muff has experienced significant growth in population during the last decade as people from Northern Ireland migrate across the border.
Each summer, usually during the first week in August, the village celebrates Muff Festival; which includes céilithe, competitions, street partying, parades, amusements, night-time entertainment, and live performances.