Holywood Motte

You'll spot it from the road - a grassy mound rising abruptly from the flat terrain just outside Belfast. Holywood Motte is what remains of a Norman fortification, built sometime in the 12th century as a stronghold during the Anglo-Norman push into Ireland. It's essentially a large earthwork with a ditch, the kind of thing that would have had wooden defences and probably a tower on top, though there's nothing left of those now.

The site itself is small and won't take long to explore. Walk round the base, clamber up if you fancy it - the views across Lisburn and Castlereagh aren't dramatic, but they're pleasant enough. It's free, which helps. History enthusiasts will find it worthwhile as a tangible piece of the Norman settlement story, though it lacks the drama of a proper castle ruin. Families with young kids might manage fifteen minutes before boredom sets in.

If you're caravan-based in the area - Dundonald Touring Caravan Park is only a few miles away - this works as a quick stop between other activities rather than a destination in itself. The Pods at Streamvale, a five-star glamping spot nearby, offers comfort if you want to make a longer weekend of exploring Lisburn's medieval heritage. Go midweek if you can, as it's genuinely quiet. Bring decent shoes; the mound can be boggy after rain.