Llyn Ogwen

The water here is proper cold and spectacularly clear - you'll spot the lake bed from the shore on a decent day. Llyn Ogwen sits in the Ogwen Valley south of Caernarfon, hemmed in by the Snowdon range, and it's the sort of place that makes you understand why people move to North Wales and never leave.

It's a walker's lake, primarily. The A5 runs right past it, so there's roadside parking and you can be on the water's edge in seconds. The main appeal is the loop walk around the shoreline - nothing brutal, takes a couple of hours at a steady pace, and the mountain views don't quit. Families with older kids will manage it fine; toddlers might find it a bit long for what it is.

There's also a small car park at Ogwen Bank, where the Caravan and Lodge Park sits just 3.7 miles away - convenient if you're staying over and fancy a morning walk before breakfast. Kayakers and canoeists use the lake regularly, and fishing is possible if you've got a licence.

The real strength here isn't an afternoon's entertainment - it's the sense of being somewhere genuinely remote while standing just off a main road. On a grey Welsh afternoon with low cloud, it's moody and atmospheric. Come on a clear day and you get the drama. Either way, the Snowdon views are free and they're excellent. Not the most dramatic lake in Wales, but certainly worth the detour if you're exploring Caernarfon and the valley trails.