Ballycastle is situated on the rugged coast of North Mayo, with its northern boundary exposed to the wild Atlantic ocean. To the west of the town are the Stags of Broadhaven (600 million years old), to the east lies Killala Bay while to the south are the towns of Crossmolina and Ballina. It was at the Céide Fields that the first settlers began to farm the slopes of the Behy/Glenurla hillside over 5000 years ago.
Farmous people from Ballycastle include the Gaelic footballer Tommy Langan. He won two All-Ireland Senior Football Championships with the Mayo GAA senior county team and was named on the Football Team of the Millennium.