Mettingham Castle College

The ruins of Mettingham Castle sit just outside Beccles, a proper medieval fortress that's been crumbling for centuries. What you're looking at is mostly flint walls and earthworks now - not the full fortress-with-turrets situation, but enough to read the story of 14th-century Norfolk life. A college was added later, which is why locals still call it the castle college, and the whole site tells you something about how power moved around East Anglia back then.

This is one for people who like poking around old stones and working out what went where. Families with young kids might find it a bit underwhelming - there's no visitor centre, no dramatic tower to climb - but older children interested in medieval stuff will get something from it. Historians will have a field day. The setting's pleasant enough, rolling Norfolk landscape, and Beccles itself is close by if you need to grab lunch or supplies.

The site appears to be freely accessible, though I'd check locally before making the trip as opening arrangements aren't always clearly posted. Allow an hour or so for a proper look around. If you're camping at Wardley Hill or Green Haven Camping nearby, it's an easy addition to a park-based holiday - the kind of thing to visit on a quiet afternoon rather than plan your whole day around. Worth a stop if you're exploring the area, but don't expect manicured ruins or grand staircases.