Castell Dinas

The walk up Castell Dinas from Crickhowell is one of those proper rewarding efforts that takes about ninety minutes there and back if you're moving at a steady pace. It's a Iron Age fort, so what you're actually clambering up to is a summit ringed with ancient earthworks - ramparts and ditches that are still clearly visible once you know what you're looking at. The views across the Black Mountains and down the Usk Valley justify every step, especially on a clear day when you can see for miles.

You'll pass through some lovely woodland on the lower stretches, which is fine when it's warm but can get properly muddy after rain. The terrain is steep in places, so it's not a casual stroll - bring proper boots and expect to use your legs. Once you're up there, the fort itself is mainly earthwork rather than standing ruins, so history enthusiasts will get more from it than casual walkers, though anyone who likes the bones of the landscape will find it interesting.

It's completely free and there's no visitor infrastructure to speak of, which means you need to be self-sufficient. An hour at the top is plenty to soak it in and have a brew if you've brought one. The campsite options around Crickhowell - Cwmdu is closest at just over four miles, or Bryndu and Pencelli Castle both nearby - make this a sensible addition to a longer walking trip in the area. Go when the weather's settled; this isn't a walk to attempt in the wet.