Cawfields Lake

The water at Cawfields is proper dark, almost black in certain light, and it sits in what used to be a quarry - you can still see the stone faces looming above if you know where to look. It's a straightforward lake walk, nothing demanding, with decent views across Northumberland moorland and on clear days you can make out the Roman Wall remains nearby. The lake itself is about a mile around, so most people take forty minutes to an hour. Families with younger kids won't struggle here, though there's not masses to do once you've done the circuit - it's more of a think-and-breathe kind of place than a theme park.

Walkers and history types get the most from Cawfields because it sits right on the edge of Hadrian's Wall country, so you can combine it with proper Wall walks if you're staying in the area. The water's there all year, but spring and early autumn are best - summer weekends get busier than you'd expect for somewhere so quiet-sounding.

You're well placed if you're camped at Herding Hill Farm or Hadrian's Wall Campsite, both within walking distance, so it works as a half-morning activity before heading elsewhere. There's no charge that I'm aware of, and parking is free near Haltwhistle. The real appeal is how it sits within the broader Wall landscape rather than being a destination in itself - treat it as one piece of a longer day out exploring the Roman sites around here.