Milecastle 36 (Carvoran)

You're standing on a stretch of Hadrian's Wall that actually feels like a proper Roman outpost, not just another crumbling stone line. Milecastle 36 at Carvoran is one of the best-preserved examples along the entire wall - a small fortification that once housed Roman soldiers keeping watch over what they considered the edge of civilization. The walls are still substantial enough to walk around and get a real sense of the layout: barracks, gateways, the works.

It's free to visit and you can turn up whenever you like, which is brilliant. Most people spend thirty minutes to an hour here, depending on how much you want to imagine the Roman logistics of the thing. The site sits right along the wall's course, so the walk itself is worth doing regardless - the Northumberland moorland around Haltwhistle is genuinely striking.

History enthusiasts will find this compelling. Kids might lose interest after twenty minutes unless they're already into Romans. If you're basing yourself at Hadrian's Wall Campsite or one of the other sites nearby - Haltwhistle Camping and Caravanning Club Site is only 2.7 miles away - this should definitely be on your itinerary. It's the kind of thing that makes sense as part of a wider wall walk rather than a standalone day out. The nearest proper facilities are in Haltwhistle itself, so plan accordingly.