Bellister Castle

The ruins sit quietly on a bend of the South Tyne, about a mile south of Haltwhistle - easy to miss if you're not looking. Bellister Castle is a pele tower, that distinctly northern thing: squat, serious, built to withstand a raid rather than impress anyone. It dates from around 1340, which makes it genuinely old, though what you find here now is mostly walls and atmosphere rather than intact rooms to wander through.

You can walk right up to it without paying anything, which is refreshing. There's no visitor centre, no gift shop, no one asking if you want a laminated guide. Just the castle, the river, and a lot of quiet. The stone is weathered grey, and sections have proper crumbled, but that's part of its appeal - this feels like archaeology rather than heritage tourism. History types will spend thirty minutes working out the layout and imagining life here in the 14th century. Families with younger kids might find twenty minutes enough; there's not a great deal of interactive stuff, just a ruin to clamber around.

The river walk is the real draw if you're staying at one of the nearby sites - Hadrian's Wall Campsite is only 2.6 miles away, or Herding Hill Farm if you fancy something a bit more upmarket. It slots nicely into a Hadrian's Wall weekend. Go early morning if you can; the light's better and you'll have the place to yourself. Bring proper shoes though - the ground's uneven and can be boggy after rain.