Arthur's O'On

A squat, circular stone tower sits alone in farmland near Clackmannan, looking rather like someone's folly got left behind. This is Arthur's O'on, a Roman bathhouse that's survived nearly two millennia in remarkably good nick - though calling it intact would be overselling things. What you're looking at is the ruins of what was likely a small hot bath built around the second century AD, probably serving soldiers stationed nearby. It's genuinely rare to find Roman structures like this still standing in Scotland.

The site itself amounts to a short walk from the road to view the stones up close. There's not much interpretation on the ground, so you'll want to bring some knowledge with you or read up beforehand. History buffs will find it worthwhile, particularly those interested in the Roman frontier and how the empire pushed this far north. Kids might find it a bit underwhelming - it's less dramatic ruin, more scholarly curiosity.

Walkers tackling the Clackmannanshire trails will appreciate the detour on a reasonable day. The landscape around it is pleasant enough, rural and quiet. It's free to visit and there's no formal opening hours to worry about, though you'll need transport to reach it properly. If you're staying at Highland Gateway Glamping just down the road, it's worth an afternoon ramble. Don't expect Instagram gold, but do expect the real thing - an actual piece of Roman Britain that's somehow made it this far north.