Ballycastle is a small seaside town in County Antrim, Northern Ireland. It is on the northeasternmost coastal tip of Ireland, in the Antrim Coast and Glens Area of Outstanding Natural Beauty. The harbour hosts the ferry to Rathlin Island and a smaller passenger and charter service to Campbeltown and Port Ellen in Scotland, with both Rathlin Island and Scotland's Kintyre peninsula able to be seen from the coast. The Ould Lammas Fair is held each year in Ballycastle on the last Monday and Tuesday of August. Ballycastle is the home of the Corrymeela Community.

County Antrim is one of the six counties of Northern Ireland, located within the historic province of Ulster. Adjoined to the north-east shore of Lough Neagh, the county covers an area of 3,086 square kilometres (1,192 sq mi) and has a population of 651,321, as of the 2021 census. County Antrim has a population density of 211 people per square kilometre or 546 people per square mile. It is also one of the thirty-two traditional counties of Ireland.