This is very interesting to visit - I came upon it by accident when walking around the harbour area. This ruin is part of the citadel built in the 17th century on the orders of Oliver Cromwell. The round turret overlooking the street and harbour was constructed in the 19th century by John Miller and is known as Miller's Folly. When Miller returned from India he acquired the Citadel and actually lived inside. It's less than a mile from the town and worth seeing if you're interested in history. read more