Calshot Castle

You're standing at the tip of a shingle spit jutting into the Solent, staring at a Tudor fortress that Henry VIII built to keep the French at bay. Calshot Castle sits bang on the water's edge near Southampton, and it's genuinely impressive - a squat, brick-built artillery fort with a central keep, the sort of place that makes you understand medieval military engineering without anyone having to explain it.

The castle itself is small enough to explore properly in 45 minutes or so. You can walk the ramparts, poke around the gun positions, and climb the keep if your knees are up for it. The views across the Solent to the Isle of Wight are proper lovely, especially on a clear day. English Heritage run it, which means the interpretation is solid without being over-the-top.

This place works best for history enthusiasts and anyone keen on coastal walks. Kids aged 8 and up will stay interested; younger ones might find it a bit confined. The surrounding shingle beach is bleak and windswept rather than touristy, which is part of its appeal.

Entry is paid (check English Heritage's website for current prices), and it's open daily most of the year. If you're based at Solent Breezes Holiday Park just 1.4 miles away, or any of the other caravan parks dotted along this stretch, Calshot works as an easy afternoon sortie. Pair it with a walk along the beach or head to Lepe Beach nearby for a picnic. It's the sort of stop that feels worthwhile without eating your whole day.