National Slate Museum

The old slate quarries around Llanberis tell the story of North Wales better than any textbook. The National Slate Museum sits right in the heart of where men spent their lives hacking stone from the mountainside, and it's properly absorbing if you give it time. You walk through the quarry itself - actual tunnels and workings - before heading into the exhibition spaces where you'll find everything from the tools miners used to photographs of the families who depended on this industry. It's not flashy, but that's rather the point.

The quarry tours are the main draw. Guides know their stuff and won't let you leave without understanding what slate extraction actually involved - the danger, the skill, the sheer relentless labour. Allow a good two to three hours minimum if you want to do it properly. Kids tend to engage well here because there's something tangible about walking through where people actually worked, but younger ones might find the historical detail heavy going after the first hour.

Entry fees and opening hours vary seasonally, so check ahead. Llanberis itself is tiny, but it's well positioned for a park-based holiday - Llanberis Touring Park and the glamping option are practically on the doorstep, and Snowdon View Holiday Park sits just up the valley. If you're staying nearby, pair this with a walk up Snowdon or time at Padarn Lake. On its own it's worth a half-day detour from Caernarfon, but honestly, if you're camping in the area you'd be daft to skip it.