Boddam Castle

The castle sits on a rocky promontory just south of Peterhead, a squat granite tower that looks like it's been glowering out to sea for centuries - because it has. Boddam's a 16th-century fortified house, though calling it romantic would be stretching it; it's more brutally practical than picturesque, all thick walls and narrow windows built to withstand both weather and raiders. You can walk right up to it and peer through the gaps, which is fine if you're into old stone and Scottish coastal architecture, but don't expect to roam around inside or find a café selling shortbread.

This is really one for people who've already got a day planned around Peterhead and fancy a bracing coastal walk rather than the main draw of a trip. The location matters more than the building itself - moorland and granite cliffs, proper north-east Scotland rather than chocolate-box stuff. Half an hour here is about right unless you're sketching it or taking a photography course.

If you're staying at Peterhead Marina Bay Holiday Park, it's a decent walk to clear your head without needing to drive anywhere. The castle sits near the Buchan Ness lighthouse area, so you could combine the two for a proper afternoon exploring the headland. Free to look at from outside, which is the only sensible way to do it. Worth a detour if you're already in Aberdeenshire hunting down castles, but don't rearrange your whole itinerary for it.