East Twin Swallet

Water disappears into the ground with surprising force here, vanishing down what looks like an ordinary hole in the limestone. East Twin Swallet is one of the Mendip Hills' more dramatic examples of how underground rivers carve their way through this karst landscape, just north of Cheddar.

Cavers know this spot well, but ordinary walkers often stumble across it quite by accident. The swallet - essentially where a surface stream plunges into caves below - sits in rough moorland that feels properly wild despite being so close to the tourist honeypot of Cheddar Gorge. When water levels are up after heavy rain, you can hear it thundering down into the darkness.

This isn't really a destination for small children or anyone hoping for facilities. It's more suited to keen walkers and those genuinely interested in geology or underground systems. The walk across Mendip to reach it can be muddy and exposed, particularly in winter.

From holiday parks like Cheddar Woods Resort & Spa or Mendip Basecamp, it makes for a decent half-day expedition if you're already exploring the area's caves and gorges. Allow a couple of hours for the round trip, longer if you're planning to combine it with other swallets nearby. Weather matters here - the exposed moorland can be grim in poor conditions.