Barnard Castle

The castle's perched on a dramatic outcrop above the River Tees, and that's the first thing that hits you - the sheer drop. Built in 1095 by Norman barons who clearly understood the value of an easily defensible position, Barnard Castle remains one of the finest ruins in the North East, managed by English Heritage.

You can walk right up into what's left of the keep, clamber along the curtain walls, and get a proper sense of medieval military architecture without the crowds you'd find at somewhere like Edinburgh. The round tower - built later in the 14th century - is particularly impressive, and on a clear day the views across Teesdale are worth the entry fee alone. Allow a good two hours if you're the type to read every placard and actually imagine the siege engines in action.

Families with children over about seven will find it genuinely engaging rather than just a "big old pile of stones". There are enough nooks to explore and sightlines to test that keep them interested. Younger kids might get restless after forty minutes.

It's free to wander the grounds from outside, though proper access to the towers costs - check English Heritage's website for current prices and opening times. The town of Barnard Castle itself is a proper little market town worth an afternoon, with decent pubs and the Bowes Museum if you need a rainy-day backup.

Stay at one of the caravan parks within spitting distance - Teesdale or Pecknell Farm are closest - and you've got a solid base for exploring the Pennine dales. Pair it with walks along the Tees Valley Way and you've got a solid week sorted.