Limekiln Cave

The limestone hollow at Limekiln Cave near Weymouth is modest but atmospheric - you're looking at a proper seaside cavern rather than the sprawling underground systems you'd find elsewhere. It's basically a worked limestone chamber, the kind of place where you can see the marks of old quarrying on the walls. The cave mouth opens onto the coastal path, and on a grey Dorset afternoon, it has real character.

Walkers will find it worth a slight detour if you're already following the shoreline between Weymouth and the Chesil Beach area. History enthusiasts might spend twenty minutes poking around, reading the rock formations and imagining the quarrying work that shaped it. Children under ten tend to lose interest quickly - it's not vast or dramatic enough to hold their attention for long, and there's no visitor infrastructure to speak of.

Getting there involves a seaside walk rather than a drive to a car park, which is half the appeal. The nearest proper base would be one of the Chesil Beach holiday parks - Waterside or Chesil Beach Lodge Park are both within spitting distance - and you can easily combine a cave visit with a morning beach walk or a stint at Littlesea if the weather turns.

It's free, it's accessible, and it costs you nothing but time. Go if you're already in the area and fancy stretching your legs. Don't plan a trip around it alone.