Ballycastle ward encompasses the coastal town of the same name and its surrounding rural landscape on the northern tip of County Antrim. The area is defined by its position between the Atlantic Ocean and the Antrim hills, with a working harbour and a long, curved beach fronting the town. Land use is mixed, featuring residential streets, local retail, and agricultural land, with the River Margy flowing into the sea at the harbour mouth.
The ward's hinterland includes the landmark of Fair Head, one of the largest basalt cliffs in Ireland, and stretches inland towards the Glens of Antrim. The landscape transitions from coastal lowlands to upland peat and moorland. Economic activity is centred on the town, with the harbour supporting fishing and seasonal ferry services to Rathlin Island, which lies visibly offshore within the ward's jurisdiction.
