Castell Dolwyddelan

The stone towers rise from a steep hillside above Blaenau Ffestiniog, commanding views down the Conwy Valley that made this a proper stronghold for the Welsh princes. Castell Dolwyddelan's two towers still stand, dating back to the 13th century, and the walk up gives you a real sense of why they chose this spot - nowhere to creep up unnoticed. The castle itself is modest compared to the massive Conwy fortresses, but that's rather the point. This was a Welsh keep, built by the locals, not imposed by Norman invaders.

The climb takes a good thirty minutes from the car park through rough ground, so wear decent boots and don't attempt it in the wet. The reward is proper hill-fort atmosphere: stone, wind, and a view that stretches for miles when the weather cooperates. History buffs will spend an hour picking over the stonework and imagining the place during its 13th-century heyday. Families with young children should think twice - it's not a casual stroll, and there's nothing to keep kids entertained once they reach the top.

If you're camping nearby - Conwy Valley Touring Park gets solid reviews and sits just 5 miles south - this fits well into a walking holiday around Snowdonia. The castle won't eat your whole day, but combined with Blaenau Ffestiniog's slate heritage or a longer valley walk, it's worth the detour. Allow two to three hours from start to finish, longer if you want to sit and soak in the views.