Carrickfergus Castle in Mid and East Antrim District

You're standing at Carrickfergus Castle, on the northern shore of Belfast Lough. Start by looking at the spot it sits on. The castle stands on a rocky outcrop that was once almost entirely surrounded by sea. The walls follow the shoreline, which gives the whole place a rough D shape. Land reclamation has pushed the water back since then, but part of the castle still meets the sea.