Giant's Hill

Giant's Hill is a proper castle mound just outside Cambridge, the kind of place that rewards a short detour if you're camping nearby at Hempsall Farm or Fen End Farm. What you're looking at is an earthwork - a raised motte that once held a Norman fortification, now crowned with trees and grass. It's not Warwick Castle, but that's rather the point.

The walk up takes minutes. The views across the Cambridgeshire fens are decent without being spectacular, and you get a real sense of medieval defensive thinking once you're standing on top. Children aged six and up will find it interesting for twenty minutes or so; younger ones might struggle with the climb, depending on how muddy it is.

Historically, this is solid stuff for anyone into Norman Britain and castle earthworks. The mound itself tells the story better than any placard could - you can actually see how the castle would have sat and dominated the landscape when this area mattered differently. It's the kind of archaeological feature that's become almost invisible because there's no gift shop attached.

Free to visit and no time constraints, which makes it ideal for a morning walk from any of the nearby campsites. Go when the ground's dry rather than after rain - the slope becomes treacherous otherwise. It works best as part of a Cambridge weekend rather than a destination in itself, but if you're already in the area, spending thirty minutes here beats another museum queue.