Fotheringhay Castle Farm

The earthworks are what get you first - massive raised banks that climb out of the flat Northamptonshire landscape like something ancient has shouldered its way up from beneath. Fotheringhay Castle Farm sits near Peterborough, and what remains is mostly those impressive mounds rather than stonework, though that's precisely what makes it compelling for anyone interested in medieval fortifications.

This is a motte-and-bailey castle site, the kind of stronghold that dominated the Norman period. Mary, Queen of Scots was held prisoner here, which gives it proper historical weight - the castle was demolished after her execution, but the earthworks have survived centuries of ploughing and weather. You can walk the site and get a real sense of how these defensive structures were laid out: the raised mound for the keep, the surrounding bailey, the strategic positioning.

It's free to explore and takes roughly 30 minutes to an hour depending on how much you're reading into the archaeology. Families with children who like clambering about will manage fine, though there's not much interpretation on-site, so bringing a decent guidebook or doing homework beforehand helps. History buffs will find it genuinely worthwhile.

Stay at Castle Farm Campsite right next door and you've basically got the place on your doorstep - brilliant for a quiet corner of a park holiday. Rockingham Forest Park is under four miles away if you want more typical holiday park facilities. Spring and autumn are best for walking the grounds without getting bogged down.