Built by Edward I during his invasion of Wales between 1282 and 1289, Harlech Castle cost the pretty modest sum of £8,190.
Over the coming centuries, it played an important part in several wars, such as withstanding the siege of Madog ap Llywelyn between 1294 and 1295, although it eventually fell in 1404 to Owain Glyndŵr, the leader of a fierce Welsh independence movement.