Michelham Priory House & Gardens

You'll spot the moat first - a proper water-filled medieval defence that still surrounds the entire complex near Lewes. Michelham Priory is what remains of a 14th-century Augustinian monastery, and the house itself dates from the 16th century when someone had the bright idea of converting the prior's lodgings into a residence. The gardens are genuinely worth the visit: there's a working kitchen garden, an apothecary's plot, and orchard walks that feel genuinely peaceful rather than twee.

Historians will eat this up. The buildings tell a proper story - you can trace the priory through the Tudor alterations, and the exhibits explain how the monks lived day-to-day. Families with kids over about eight will find plenty to do, though younger ones might get bored once they've splashed about the moat edge. The rope-making demonstration (when they run it) is excellent.

It's a gentle half-day job rather than a full day out. Allow a couple of hours if you're thorough, less if you're just wandering the gardens. Entry isn't free, but it's reasonable for what you get. The site works perfectly as part of a Sussex park holiday - you're within spitting distance of Lewes itself, and Golden Cross Holiday Park and Fontmills Farm Campsite are both very close by. Head there on a quieter weekday morning if you can; summer weekends can get properly rammed with school groups.