Donaghadee Marina

The waterfront at Donaghadee has that proper working-harbour feel - fishing boats, leisure craft, the smell of salt and diesel fuel. You can walk the full length of the marina, watch the boats come and go, grab a coffee at one of the cafes lining the quay. It's not a theme park, and it won't keep young kids entertained for hours on end, but it's exactly the sort of place you pop into for an hour while staying nearby.

The town itself is quiet, old-school seaside charm without the kiss-me-quick hats. There's a lighthouse you can visit if you're keen on maritime history, and the pier walk is genuinely lovely on a clear day - you get views across the Irish Sea towards Scotland. For families based at Dunroamin Caravan Park in Millisle, just down the road, this is an easy morning outing. Sandycove Holiday Park, slightly further out, works too if you don't mind a short drive.

Go when the weather's decent. A grey, windy afternoon here is just wind and concrete. But on a sunny morning with the boats bobbing and the light hitting the water right, you'll understand why locals bother. Free to wander, though you'll likely spend a tenner on lunch. Give yourself ninety minutes max unless you're genuinely into boats.