Caban Coch Dam

Drive up the Elan Valley from Rhayader and you'll round a bend to find yourself staring at one of Wales' most imposing Victorian engineering feats - Caban Coch Dam. It's a proper sight, this one. Built in 1904 to supply water to Birmingham, the dam curves across the valley in red stone and is genuinely monumental when you're standing in front of it.

There's a decent walk along the top - takes about twenty minutes at a leisurely pace - and the views back down the reservoir are lovely on a clear day. The valley walls close in around you and you get a real sense of the scale of the thing. It's not the kind of attraction that'll keep you entertained for hours, mind. Expect forty-five minutes to an hour unless you're keen on the history of Victorian water engineering or fancy exploring the surrounding footpaths.

History buffs will appreciate what this dam represents - part of a radical Victorian scheme to transform Mid Wales into a water source for England. Walkers will find it a decent waypoint on a larger route through the Elan Valley, which has multiple reservoirs and forest trails nearby. Families with young kids might find the views a bit static after a quick gander, though older children curious about engineering will get more from it.

The fact that it's free and accessible from the Rhayader side makes it a solid stop if you're camping at Elan Oaks or The Pines. There's limited parking and few facilities, so go mid-week if you can. Worth the detour if you're in the area, but don't rearrange your holiday around it.