Swansea Castle

The ruins sit right in the heart of Swansea's city centre, squeezed between the marina and modern shops - you can't miss the crenellated stone walls rising up from the pavement. What's left is mostly the keep and fragments of the outer defences, built by the Normans in the early 12th century as a statement of power. You can wander around the grounds free of charge, peer through the windows into the keep, and get a proper sense of how imposing it must have looked when intact.

This isn't Caernarfon or Conwy - don't expect intact towers or a lot to explore. The castle's been battered by centuries and urban development, but there's something rather honest about that. History types will appreciate the Norman architecture and the layers of conquest visible in the stonework. Kids might manage twenty minutes before they've seen the lot, though they can clamber about on the grassy mound and take photos from the walls.

If you're based at Swansea Marina Tourer Park, you're practically on top of it - a five-minute stroll. For those staying further afield at Riverside Holiday Park or Gowerton, it's worth combining with a proper walk around the seafront and marina. The real draw of Swansea is the bay itself and the Gower Peninsula beyond, so slot the castle in as a quick cultural punctuation mark rather than a destination in itself. Go midweek to avoid the shopping crowds.