West Grotto

You'll find yourself squinting into darkness the moment you step inside this underground chamber near Dunkeld - and that's rather the point. West Grotto is a genuine 18th-century folly, the kind of thing wealthy landowners commissioned when they wanted to impress visitors with their sophistication and oddness in equal measure.

It's essentially a vaulted stone chamber carved into the hillside, decorated in that peculiar Georgian way with shells, pebbles, and bits of coloured glass embedded into the walls. The effect is somewhere between a grotto and a very elaborate garden shed. You can walk inside - mind your head on the low ceiling - and spend a solid ten minutes examining the shells and wondering what the original owner was thinking.

This works best for people who like geological oddities and 18th-century eccentricity. If your kids are hoping for interactive displays or anything flashy, they'll be disappointed within minutes. Historians and folly enthusiasts, though, will find it genuinely absorbing.

Allow maybe thirty minutes if you're thorough, less if you're just ticking it off. It's the kind of thing you'd visit as part of a broader Perthshire walking tour rather than a destination in itself. Since Dunkeld is right there - a proper attractive riverside town - you could easily combine it with a riverside walk and a decent lunch.

Stay at Inver Mill Farm Caravan Park, just a short drive away, and you've got a solid base for exploring this corner of Tayside without feeling trapped at the accommodation.