Monknash, South Wales
Located close to Llantwit Major on the south coast of Wales, this small bay is one of this areas hidden gems. To get to the bay you need to take the small road down towards the coast at the Plough and Harrow pub in Monknash. This will take you most of the way, but you have to park in a field opposite New Mill Farm just before a very sharp right-hand bend, with an honesty box for payment.
Once parked you need to walk down the road, and then left onto a footpath that follows the river (Cwm Nash) down to the sea. This path can be a little slippery, and takes around 20-30 minutes to get to the sea, but it's well worth it. Once on the beach you'll find a small waterfall surrounded by craggy cliffs.
Being west facing, it's best to visit at sunset and when there's a reasonably high tide (although not the highest tides as this can reach the waterfall). Just watch out for breaking waves, especially in high winds, which can make it tricky to keep dry. Being part of the Bristol Channel, the tidal range is extreme, so at low tide the sea can be a long way from the cliffs.