Published 16th July 2011

Need to get away from it all? The only way is Essex

But, peering down, I can see a gravel driveway of sorts, green seaweedy slime down the middle, weaving a wiggly mile across the mud flats to the island of Osea. I nudge the car forward, feeling a bit like a motorised Moses crossing the Red Sea and fearing that at any minute a tide change will sweep my vehicle away — which could happen if you get the timing wrong: there is only a four-hour window in which to make the crossing every 12 hours.

It’s this causeway, first developed by the Romans (who failed, though, to build it straight) that makes Osea so special. You can drive there but still feel cut off from the world. Better still, this secret island haven — I’d never before heard of it and I live 20 minutes away — is just over an hour from London, in the Blackwater Estuary, Essex.

Down another gravelly lane, this one on land and flanked by kamikaze bunnies who dart before the car, we come to a cluster of weatherboard cottages with picket fences, which this year opened as an exclusive resort; you have to be a guest here to enter Osea. What’s more, once you get there, it’s a car-free zone, so children can run freely around the tiny haven. It’s only 1½ miles long and half a mile wide, and is encompassed within a four-mile stretch of pebbly coastline. It’s a piece of yesteryear.

It’s hard to believe that, until recently, the island was a rehab clinic called The Causeway Retreat, where the likes of Amy Winehouse would pay up to £10,000 a week to take lungfuls of estuarine air rather than lungfuls of more lethal substances. That was not the first time that the island had been a base for those trying to cure addictions. It was also the home to an experimental temperance society under one Frederick Charrington, who, after buying it in 1903, constructed most of the buildings you see there today, including the splendid manor house and a village store.

The store has closed long since — you need to take your own food — but the area where most of the cottages are located is still called the village — its red postbox charmingly states that collection times are “according to the tide”.

It is here that we meet the island’s owner, Nigel Frieda, the brother of the hair stylist John Frieda, and successful in his own right as the owner of Matrix studios, used by bands from the Rolling Stones to Oasis, and as former manager of the Sugababes.

“I used to rent a cottage here as a bolt hole from London and I fell in love with the place. I’d find a weekend would completely recharge my batteries,” Frieda says. “I never thought I’d own it.”

One £6 million purchase later, he still spends many of his weekends here, having imposed his own style on the properties. And what style. They have been done up beautifully, with crisp cotton sheets and faux fur throws on four-poster beds, slipper baths, leather Chesterfields and oversized sofas. The most luxurious is the Manor House, which sleeps 20, and comes with its own recording studio and Beduin tent, but the ten cottages and seven apartments all bear the same design traits. The shabby-chic tone means that wood-burning stoves are found alongside plasma TVs, and there is great attention to detail, with a magnifying glass here, a telescope there and books everywhere.

“I furnished them as somewhere I would want to stay,” Frieda says.

But, however comfortable the cottages are inside, Osea is still about the big outdoors and its simple charms. And so, for a few days, my five-year-old son and I live an Enid Blytonesque existence, jumping on and off our bikes, throwing them down and knowing that they’ll still be there four hours later. We hike along the coastline, heading round by the sea wall through wooded glades, cutting across to pebbly beaches and wide expanses of salt marsh, where the receding tide leaves riverlets of water and crabs scurrying sideways over the mud.

We fish for the sea bass that we see jumping from the water but they only nibble on our bait, so we munch instead on samphire, the salty plant used by posh chefs in their posh restaurants. It grows abundantly here in the estuary mud.

This is oyster-farming country — it’s only a 20-minute boat ride to the island of Mersea, renowned for its seafood restaurants. If you look hard you can see shells clumped on the mud flats off the causeway, ready for plucking. Boats are part of everyday life, whether it’s simply watching the historic barges sailing sedately past or hiring a dinghy or kayak to go exploring.

Not that you need to venture off the island to find something to do — there is a heated pool, tennis court, a games room with mini cinema, a well-equipped gym and the added attractions of the donkeys Salt and Pepper, and Cyril the dog, who follows us when he feels like it.

We find a V2 bomb that the Germans aimed at London, and clamber over one of two pill boxes on the island. Osea, it turns out, has a strong naval history; in the First World War more than 1,000 sailors were billeted on this top-secret naval base for motor torpedo boats.

We return happy but tired each night to our cottage, one of two away from the main village area, which have lovely sea views. At dawn and dusk we watch the rabbits socialising on the lawn, though we fail to spot any of the five species of British owl that are resident on the island.

On our last day we cycle back to the causeway, where we delight in spying crabs scuttling under displaced rocks before we sit on the beach to watch the tide creep over the land that we were walking on half an hour before. A tractor rushes over, splashing through the encroaching water, and a family of three on bikes only just make it back to the mainland before the causeway becomes nothing more than two thin snaky lines of bladderwrack. Minutes later it is completely submerged.

We are cut off from the rest of the world, and it feels amazing.