The Bullstone (Site of Castle)

All that's left of the medieval castle at Bullstone is a mound and a few stones, but that's rather the point of archaeology - you're reading a landscape like a book, and this one tells of Norman ambition and centuries of neglect. The site sits near Looe, that charming fishing town on Cornwall's south coast, and it's the sort of place walkers stumble upon rather than plan around. There's no visitor centre, no interpretive boards really spelling it out, which means you either come prepared with a bit of local knowledge or you wander up and find yourself standing on what amounts to a very old bump in a field.

This works best for history buffs and walkers who like their attractions off the beaten track - if you're expecting a castle to actually stand there, you'll be disappointed. Allow twenty minutes, maybe half an hour if you're the sort who likes to sit and imagine what it all looked like eight hundred years back. The climb is gentle enough, and on a clear day the views over the surrounding countryside are proper decent. Looe itself is worth a full day for the harbour, the fish and chips, and the coastal walks, so you might tack this on as a morning ramble if you're based at one of the holiday parks nearby - Lydcott Glamping or Waterside at Tregoad are both within easy driving distance and well-reviewed. It's free to visit and open whenever, which is how these things tend to work when there's precious little left to guard. Don't expect crowds or facilities, but do expect a quiet corner of Cornwall's medieval past.