St Catherine’s Fort lies on a small island just off the coast of Tenby in West Wales. It was built in the 1860s to protect the Pembrokeshire coast from possible invasion by France. There are gun embrasures down both the Northern and Southern sides. It was never called to action and was eventually sold and has been many things since including a zoo. While it is now inaccessible to the public it is an impressive structure and is easily visible from the South Beach.
Military - Historic - Forts and Batteries
Links: en.wikipedia.org, www.clash-of-steel.com