Lydstep Haven

Lydstep Haven is a big, gently curving bay of clean sand facing south across Carmarthen Bay, with Caldey Island out to the east and limestone headlands closing it at both ends. It's shallow, sheltered and one of the calmer swimming beaches on this coast. The complication is access: the bay is part of a private holiday park, and getting to the sand normally means going through the park. Arrangements change, so check the current position before driving there — turning up expecting a public car park can end badly.

If you're staying in the park, or you've established that access is available, it's an excellent family beach: a long flat sand at low tide, safe paddling, and enough space that it never feels crammed. It's unguarded outside of any cover the park may provide, and while the bay is benign compared with the open Atlantic beaches, the tide comes in across flat sand at a fair pace.

The land above the bay is National Trust: Lydstep Point and Lydstep Headland give a short clifftop circuit with wide views, and it's free and open to anyone. Along the western headland are the Lydstep Caverns, sea caves reachable at very low tide from the beach — spectacular but genuinely risky, and not something to attempt without local knowledge and a tide table. Manorbier is five minutes' drive west, Tenby ten minutes east, and both make easier day-to-day beach bases.