Mile Castle 59

The Roman fort at Mile Castle 59 sits squat and stubborn on the Northumberland Wall, about four miles south-west of Carlisle. What you're looking at are the foundation stones of a small garrison fort built around 130 AD, positioned precisely one Roman mile from its nearest neighbours along this defensive line that once stretched across northern Britain.

There's not much left standing - you're essentially looking at ground plans and wall footings - but that's precisely what makes it worthwhile for anyone interested in how the Romans actually lived on the frontier. This wasn't some grand showpiece like Hadrian's Wall proper; this was functional, military architecture. You can walk around the perimeter in about twenty minutes, trace where the barracks would have been, spot the ditch systems that protected against raids from the north.

History types will find it compelling. Kids might manage ten minutes before restlessness sets in, unless they're the sort who find archaeology genuinely exciting. It's free and accessible year-round, though the Cumbrian weather can be dreary in winter - go on a clear day if you can.

It works brilliantly as a stop en route to Carlisle itself, or combine it with other Roman sites in the area. If you're based at Green Acres Caravan Park nearby, you've got a proper cluster of archaeological interest within reasonable driving distance. The site sits on open moorland, so dress for wind and bring waterproofs. Don't expect crowds.