Colchester Castle

The square Norman keep rises from the town centre with genuine weight - you can't miss it, and frankly you shouldn't. Built by William the Conqueror's man Eudo Dapifer right after 1066, Colchester Castle sits on the foundations of a Roman temple, which tells you everything about how long this place has mattered. Inside, the museum walks you through layers of actual history: Roman pottery, Saxon jewellery, the works. The keep itself is the draw - climb the stone stairs and you're rewarded with proper views across Colchester and Essex beyond. Allow a solid two hours if you're going to do it right, less if you're just popping in for the views.

Families with kids over about eight will get something from it - younger ones find the climb tedious and the exhibits a bit dry. Serious history types will spend longer picking through the detail. It's free to wander the grounds, though admission to the keep and museum costs a few quid. Go mid-week if you can; weekends bring school trips and it gets crowded.

If you're based at Colchester Country Park just down the road, the castle makes an easy half-day out when the weather turns. It's a proper rainy-day option too. Ardleigh Caravan & Camping Park, three miles south, puts you close enough for a quick visit without eating into your whole day. The town itself has decent cafes and shops if you want to make an afternoon of it.