Llyn y Gran Fawr

The walk down to Llyn y Gran Fawr is what sells it - a proper moorland trudge through Powys that feels genuinely remote even though Brecon is only a handful of miles away. Once you're there, you get a high-altitude reservoir surrounded by open hills, the kind of place where you can actually hear yourself think. The water's dark and serious-looking, hemmed in by rough grass and rock rather than anything manicured.

It's worth the trip if you're the type who enjoys a decent walk and doesn't need a visitor centre or café to feel like a day is well spent. Families with younger kids might find it a slog - there's no easy payoff at the end, just a lake and views. Walkers, though, will find it bracing. The hills around here are proper Brecon Beacons territory, so the landscape justifies the effort.

All of this is free, and there's no specific opening hours to worry about - you're just going to a lake. Allow a couple of hours minimum, longer if you're the type to sit about looking at the view. Go in decent weather because in cloud or rain it becomes less rewarding and genuinely exposed.

If you're staying at Cwmdu Campsite, it's close enough for a half-day outing, though you'll need the legs for it. It works well as part of a broader Mid Wales hiking trip rather than a standalone destination.