Beyond the glass wall of the shepherd’s hut, a vast flat landscape stretches to touch wide open skies. A yellow wagtail takes wing in a flash of colour and the long grass quivers as a hare emerges, glances our way and then scarpers. To the east lie salt marshes, mudflats and glistening waters of the Swale, a tidal channel of the Thames estuary, its far bank dotted with industrial buildings, adding an edginess to the stark natural beauty.

Elmley nature reserve on the Isle of Sheppey in Kent is just over an hour from London, yet there’s a sense of peaceful isolation. The 3,300-acre site is the only family-owned and managed national nature reserve in the UK – Georgina Fulton, daughter of pioneering farmers and conservationists Philip and Corinne Merricks, runs it with husband Gareth – and it’s the only one you can stay overnight. By day it welcomes walkers and birdwatchers; stay on, though, and you’ll have it all practically to yourself.

Facebook Twitter Pinterest A bedroom at newly opened Elmley Farmhouse

We arrive late afternoon, via a bridge from the mainland – until the 1940s a ferry was the only way across. As islands go, Sheppey isn’t a conventional beauty; a medley of marshland, industrial sprawl and holiday camps, it is the butt of many a Kent mainlander joke. But as soon as we turn into Elmley’s two-mile driveway – made by Canadian soldiers garrisoned here during the second world war – I’m bewitched by its empty, echoing charm and darting birdlife.

There are six huts to stay in on the reserve. Made of sustainable wood or corrugated iron, with epic views and nice touches like hot-water bottles and chunky woollen throws (some have kitchenettes too), they are spread out to ensure privacy and full nature immersion. The reserve’s 18th-century farmhouse is now open after renovation: marrying sweeping views of the reserve to a high-spec modern kitchen with glamorous vintage vibe, it can be rented in its entirety (sleeps 12, plus two children) or as individual rooms for B&B stays during the week. There’s a new cottage too, sleeping 10, with wraparound windows and a spacious living area. At the heart of the reserve is a beautiful 19th-century barn: popular for weddings, it also serves as a communal space for guests with board games and movie projectors for rainy days, and there’s an honesty bar stocked with local wines and beers. Solar energy powers the whole place.

Facebook Twitter Pinterest Starlings over Elmley nature reserve

After checking out the hut we’re staying in, the Ferryman’s (with room, too, for a couple of kids on a hammock or pull-out bed, and an outdoor shower as well as indoor bathroom), we’ve time for a pre-dinner stroll through Elmley’s wildlife-rich marshes and meadows. We follow a gravel track along the seawall to the first of the reserve’s four hides and gaze out over one of the most important sites in the UK for breeding waders. In winter, tens of thousands of lapwings (a particular success story here), redshanks, golden plovers, teals and wigeons fill the skies, while short-eared owls are also common; birds such as oystercatchers and marsh harriers can be seen here all year round while autumn sees migrants such as green sandpiper and whimbrel stop over en route to Africa.

Further on, other hides offer more unbroken views over shallow ponds, wetlands and grasslands. Spitend Hide, on the eastern tip, overlooks the Swale Estuary – and those who make the 3½-mile walk will find a hamper there filled with blankets and treats. We wander back before nightfall, clouds of dragonflies dancing in the early evening light, the sound of marsh frogs filling the air.

There’s no on-site restaurant at Elmley but homecooked meals, made using local produce, can be delivered in hampers to your hut. We dine outside on delicious rich veggie and beef stews and chocolate cake, sitting around the firepit as the stars come out, and sleep with the curtains open, waking to see the sunrise.

Facebook Twitter Pinterest The Edith May restored Thames barge. Photograph: Jane Dunford

After breakfast Gareth takes us on to the Swale on his boat to visit the Edith May, a spectacular, restored 1906 Thames barge which recently started offering sailing trips (from £15). Barges like this were once used to transport grain and bricks along the Swale to the centre of London, returning with horse dung for the fields. (Thames barges were the last trading vessels in Europe to carry cargo under sail alone, finally finishing commercially in 1970.) It’s a great way to take in the wild expanses of a corner of Kent that deserves more love.

• The trip was provided by Elmley Nature Reserve. Huts sleeping two to four start at £95-£130 a night (two-night minimum weekends); Elmley Cottage sleeps 10, from £560 for two nights; Kingshill Farmhouse sleeps 12+2, from £1,900 for two nights

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