Llyn Bochlwyd

The walk in to Llyn Bochlwyd is half the appeal, and honestly, it's a proper slog. You're looking at a steep climb through the Ogwen Valley from near Caernarfon, gaining height steadily until the landscape opens up and this dark mountain lake appears below you like someone's switched the world into focus. The water's cold enough to take your breath away if you're mad enough to swim, and the rocky shores mean you can scramble right down to the edge without faffing about with beaches.

It's a walker's lake rather than a casual visitor spot. The views back down the valley are exceptional once you've earned them, and on a clear day the surrounding peaks frame it beautifully. There's no facilities up here, no café, no visitor centre - just you, the water, and the mountains. Families with decent-aged kids will manage it fine, but toddlers will be miserable after twenty minutes of climbing.

Timing-wise, allow three to four hours for the round trip depending on fitness. Early morning is best to avoid the afternoon crowds, and spring or autumn beats summer when it gets rammed with Instagram types. Winter's quieter still, though the paths get slippery.

If you're based at Ogwen Bank Caravan and Lodge Park nearby, this is the natural morning activity before breakfast. It's free, obviously - just park sensibly and respect the farmers' land. Worth doing once? Absolutely. Making a day of it? Only if you're genuinely keen on walking.