Allen Banks & Staward Gorge (National Trust)

The Tyne Valley cuts through here with real drama - steep wooded banks dropping down to a proper gorge where the river churns below. Allen Banks is National Trust land, which means it's well maintained but feels genuinely wild once you're down in the trees. The walk takes you through riverside woodland, past old industrial ruins (there's lead and ironworking history scattered about), and if you're up for it, across Staward Gorge itself where the cliffs rise up sharp and the water runs fast.

This is walkers' territory, mainly. Families with older kids who don't mind muddy paths will find it engaging - the gorge has proper atmosphere, not a manicured experience. The ruins add a puzzle element if you're into that sort of thing. Young children might find the walk a bit relentless, and you'll need proper shoes because it gets slippery.

It's free to access and you can spend anything from an hour pottering about to a full morning if you tackle the longer circuits. Go when the water level's up after rain - the gorge looks far more impressive. Hexham's right there for supplies and a decent lunch stop. If you're camping nearby - Herding Hill Farm or Hadrian's Wall Campsite are close enough for an easy morning visit - this fits perfectly into a Northumberland walking holiday. Not showy, but genuinely good.