Llyn Ddu

A proper mountain lake that sits quietly in the Gwynedd hills, Llyn Ddu rewards those willing to walk for it. The water is dark - hence the name - and reflects the surrounding peaks in a way that feels almost too good to be true when you first round the bend and see it. Most people approach from Porthmadog direction, and it's not a casual stroll. Allow a good couple of hours for the walk in and back, longer if you want to sit and actually enjoy the place.

This is one for walkers and photographers, really. Kids might find the trek tedious unless they're the outdoorsy type, but if you're staying at Ty'n Llan Camping nearby - and it's excellent - you could easily make this a half-day adventure. The lake itself isn't huge, so don't expect to potter about for hours once you arrive. It's more about the journey and the moment when you finally see the water spread out below you.

There's no cafe, no facilities, nothing commercialised about it. Free access as far as I can tell, though weather can turn quickly up here so pick a clear day if possible. It's the sort of place that stays in your head after you've left - not because it's remarkable in scale, but because reaching it feels like you've found something that hasn't been spoilt. Pair it with Black Rock Sands if you want a beach day to balance out the walking.