I stayed in my own castle in the middle of the sea for just £23 a night & ate oysters from the beach for dinner

THERE aren’t many places in the world where you can bed down for the night in your own castle or fort from just £23 a night.

But incredibly, it is perfectly possible to bag a stay in an ancient fortification with stunning views and centuries of history in its thick, stone walls.

Jersey Heritage Lets features a host of island-owned fortresses and towers on the Channel Island gem you can stay in, some of them pretty rustic, some of them pretty fancy, all of them with a story attached.

They range from a beachside folly which looks like an upside-down barge, ideal for sunset yoga, to a brutalist German WWII radio tower which looks like it belongs on a submarine.

You get a whole lot of experience for your money in these places, especially if you choose Seymour Tower, the portfolio’s stand-out property.

This four-storey watchtower of four-foot-thick granite was built out on a reef 1.5 miles from the shore back in 1782, to keep an eye on the French.

That makes it the ultimate coastal retreat, with the sort of sea views that are to die for.

You do need to be careful not to actually die, though.

The island of Jersey has one of the biggest tidal ranges on the planet, growing by 50 percent at low water.

Despite Seymour Tower looking like a pimple on the horizon, you can easily walk out to it at low water, but you do need a guide to ensure you don’t miscalculate.

I tried out the Seymour experience this spring, with guide Jerome, collecting oysters for our dinner en route, but avoiding those with a milky white seam. “We don’t want to eat the spermy ones,” said Jerome. Quite.

Once we’d arrived, he called the coastguard from the top of the tower to let them know we were in residence.

Meanwhile I found myself muttering, ‘I am the king of the castle, and you lot are all dirty rascals’. Not that there was anyone around.

Looking back to dry land, the tide had already started its pitch invasion, sidling up through the seams and gullies.

Within an hour it looked as if the water was trying to throw a cloak over an army of frothy sea monsters, as all the reefs slowly disappeared.

Despite its castaway location, the tower is comfortably if rather rustically equipped. Think seaside shabby chic. Its main living space has a wood burner, gas oven, and rainwater sink.

The electricity is solar powered, and very necessary in a tower with tiny loophole windows. “Do you want the wifi code?” joked Jerome. “It’s f*** off”.

A hatchway in the middle of the main floor opens down into a cellar. On the floor above are eight basic bunk beds (bring your own sleeping bag), then the top floor has a composting loo and a roof terrace.

After supper of grilled oysters with cheese, we returned to that top terrace to savour the magnificent 360 degree view.

From the seaward side, a handful of reef lights were winking conspiratorially at us.

That night I woke only once. We’d gone to bed at the height of the tide, with the hungry sea monsters bashing a drum in the cellar and their friend, the wind, rattling the door.

I woke in the early hours thinking that something was wrong, and it took a moment to realise what: silence.

The tide had gone. I could just about make out a distant murmur, like an audience starting to assemble in a theatre for the next performance.

Next morning, after returning to the mainland when the sea allowed, I headed west, to where another of the Heritage properties stands on the headland at La Pulente, overlooking the iconic Corbière lighthouse.

The Radio Tower is unmistakably Germanic, but there are no pellet loos here: this outpost has been comfortably refitted.

A winding spiral stair leads up to its best bit, the glass-walled lookout, equipped with a dining table and sofas and one of the best views of any accommodation anywhere in the world.

Sitting up here, in the year that is the 80th anniversary of Jersey’s liberation, I found myself wondering what the German radio officers had made of it.

Surely a view like this, with the sun dropping slowly behind Corbière, was enough to make even the hardest soldier go all misty eyed.

It certainly did it for me. After Seymour I appreciated the Wi-Fi and the hot water, too, but with no access to free oysters, I had to get in the car and go in search of chips for tea.

There's plenty of other ways to be king of your own castle in the UK. The Landmark Trust has a host of crenellated castles you can check in to.

Cawood Castle in North Yorkshire was once the residence of the Archbishops of York. It was here Cardinal Wolsey was arrested for treason on Henry VIII’s orders.

Today, just the gatehouse and domestic wing of the castle remain and you can enjoy a stay in a beamed cosy apartment sleeping four with stairs leading up to a flat roof where you can look out from behind the crenellated walls to the surrounding Yorkshire countryside.

Four nights’ self-catering is from £344 in total - or £21.50pp, per night.

For stunning sea views, Kingswear Castle in Devon is another medieval gem, built to help the larger Dartmouth Castle defend the harbour.

Landmark have restored the castle’s ground floor to look as it did back in 1502 with cosy, modern living quarters above sleeping four.Four nights self-catering is from £844 in total - or £55.25pp, per night.

For a castle with real wow factor, Astley Castle in Nuneaton, Warwickshire combines modern architecture with an ancient, moated palace.

Stitching modern rooms into the ruined walls, the restoration won the RIBA Stirling Prize for Architecture. Sleeping eight four serene, light-filled rooms the castle’s original walls are the star of the show.Four nights’ self-catering is from £1,504 in total - or £47pp, per night.

For all properties, and more, see landmarktrust.org.uk.

And if you’re after a castle that can cope with a crowd, Big House Experience has some stunning castles to rent.

Stonegate Lodge is a 500-year-old estate in Essex set in 350acres of parkland. The 11 bedrooms sleep up to 22 people and there are plenty of facilities including two kitchens, two living rooms and the Rochester Suite, a large entertaining area.

Of course, there’s also all the classic castle features you'd expect from huge fireplaces and arched stone windows to flagstone floors and quirky antiques.

Three nights’ self-catering is from £6,375 in total - or £96.50pp, per night.

Pengarth Castle on the edge of the Eryri National Park in Wales is a classic castle with stone crenellations and stunning estuary views set in 40 acres of private grounds.

Sleeping 22 in 11 bedrooms, there’s a grand entrance hall with carved oak staircase as well as a wood-panelled billiards room and dining room with a magnificent glass ceiling.

Three nights’ self-catering is from £4,850 in total - or £73.48pp, per night.

For these properties and more, see bighouseexperience.com