Nothe Fort

Walk out along the Chesil Beach and you'll spot this Victorian fortress commanding the entrance to Weymouth Harbour. Nothe Fort is a proper bit of 19th-century military engineering - all ramparts, gun emplacements and that distinctive low profile designed to withstand bombardment from warships. The fort dates from 1860s anxiety about French invasion, which feels both oddly reassuring and slightly absurd now.

You can wander around the outer walls and peer into the gun casemates without paying anything, which is the best way to experience it if you're short on time. The views back across Weymouth and along Chesil Beach justify the walk alone. On a clear day you're looking out to Portland, and the whole sweep of Dorset coastline fans out behind you.

Histories types will get more from it than casual visitors, especially if you can grab information about its role in the Second World War. Families with kids of eight and up enjoy the defensive structures and the beach access, though there's not much to actually keep them occupied for more than an hour. The walk from Rodwell is scenic but exposed - bring a windproof.

If you're staying at any of the holiday parks near Weymouth - Chesil Beach Lodge or Haven Weymouth Bay are closest - this works perfectly as a morning expedition before the beach crowds arrive. It's free, you can do it in ninety minutes, and it adds a bit of substance to what could otherwise be a standard seaside day.