National Trust - Boarstall Tower

The tower itself is rather squat and unprepossessing - a chunky brick keep surrounded by a moat that's more boggy ditch than dramatic water feature. But that's rather the point. Boarstall Tower is genuine medieval, the real deal, built sometime in the 14th century as a gatehouse to what was once a much grander hunting lodge. What you get now is the tower, a few outbuildings, and a lot of National Trust atmosphere.

Inside, it's genuinely cramped. Three storeys of cramped, actually, with narrow staircases that'll have you turning sideways. The rooms are small, sparse, and somehow all the more authentic for it. There are displays about the tower's history - it survived the Civil War, got altered during the 18th century - but this isn't a grand interpretive centre. It's a tower. You walk around it, climb it, and that's largely that.

History enthusiasts and those fond of medieval structures will find it worthwhile. Kids might manage an hour, less if they're impatient with stairs. The surrounding countryside is pleasant rather than spectacular - you're on the edge of the Oxfordshire Cotswolds here, not far from Aylesbury. If you're camping at Weston Caravan and Campsite just down the road, it's a decent half-day jaunt to break up a holiday. Admission and opening hours vary, so ring ahead. The moat walk is free regardless, which is honest work for the effort it takes.