Havenside Country Park

The Wash opens up before you at Havenside - that vast, muddy expanse of tidal marshland where Lincolnshire proper gives way to something wilder and altogether less forgiving. It's a nature reserve that demands you come with proper binoculars and patience, not expecting Instagram moments but actual wildlife. Waders, wildfowl, the occasional seal hauled out on the mud banks - this is genuine habitat, managed for creatures rather than visitors.

The walk itself follows the river edge, flat as you'd expect from these parts, with wind that cuts straight off the North Sea. Allow a couple of hours if you're serious about spotting things; less if you just fancy a breath of air and a stretch. Bring waterproofs - the ground squelches after rain and the weather turns in minutes. Families with young kids might find it a bit bleak unless they're already keen birdwatchers; older children who can sit still and look through binoculars will have a proper time of it.

Boston's only a few miles south, so it slots neatly into a caravan park holiday. Orchard Holiday Park and Appletree Holiday Park are both close by, and if you're after something with more edge, Big Sky Hideaway's glamping is actually well-rated. The reserve itself is free to wander - no admission charge that I can find - and there's car park access. Go at dawn or dusk in spring and autumn for the best chance of seeing migrants. Summer's quieter for birds but the light lasts forever. Worth a morning if you're based locally; don't drive an hour specially for it.