West Martello Tower

The tower itself is a sturdy red-brick affair, built during the Napoleonic Wars when Britain was convinced the French might actually invade from across the Channel. It sits just outside Milford Haven, that working port town where the industrial grit of Wales meets the sea - not exactly Instagram-friendly, but honest.

What you're looking at is a Martello tower, one of around 100 that pepper the British coastline. This one's circular, squat, and designed to be difficult to attack. You can walk around it, peer at the architecture, and if access is granted (it's not always open to the public), you might get inside to see the gun positions. The real draw is standing where soldiers stood two centuries ago, watching for naval threats that never came.

It's the sort of thing history buffs will linger over for half an hour, photographing the masonry and imagining the view from the gun platform. Kids might manage ten minutes before asking what's for lunch. There's no visitor centre, no café - just the tower and whatever stories you bring with you.

If you're based at one of the nearby caravan parks - Grass Roots is closest at under two miles - it's a decent leg-stretch between Pembrokeshire's more obvious attractions. Park yourself at Windmill Hill near Pembroke if you want something central. The tower works best as a historical appetiser before heading to Tenby or exploring the Pembrokeshire Coast Path. Don't detour specially for it, but if you're already in the area, it's worth ten minutes of your time.