Parliament House Cave

You're scrambling across rocks on the Anglesey coast near Holyhead, salt spray in your hair, when you spot the cave entrance - Parliament House Cave, a proper sea cave carved into the cliffs by centuries of Atlantic waves. It's not a vast underground cathedral, but rather an intimate cavern you can actually walk into and explore, with the sound of water echoing off the stone walls. The cave gets its name from local legend; apparently it was used as a meeting place, though honestly the real draw is standing inside watching the sea crash just beyond the entrance.

This works best for families with kids old enough to navigate rocky foreshores safely - little ones might struggle with the uneven terrain and scramble involved. Walkers and geology types will find it genuinely interesting; the rock formations tell a story about coastal erosion that no museum display can match. Allow 30 minutes to an hour including the walk down and time to poke around inside. It's free, obviously.

Access depends entirely on tides - you need to time your visit when the water's out, so check tide times before heading over. The cave is best visited on a calm day; rough seas make the approach properly dangerous. If you're staying at Coastal Pods or Two Peas in a Pod near Holyhead, it's practically on your doorstep and worth squeezing in. The beauty of Parliament House Cave is you're not trapped in a tour group; you get the place to yourself most days, standing in actual history while the sea does what it's done for millennia.