Trail of the unexpected: Jersey

It's been so easy. Easy flight (though note, not, for me, the easy airline, which now serves the island only from Liverpool). Quick, painless baggage collection. Car-hire desk steps from the arrivals gate, and car itself practically outside the door. A left turn out of the airport, right down the hill, and there is the Atlantic in all its holiday glory, crashing splendidly on the harbour rocks like a splash of cold water to the face.

It's the weekend, and all of a sudden I'm in Jersey. The weather here, though milder than the British mainland, does not come with a sunshine guarantee. But somehow here the greyness doesn't have the same oppressive hold as it does on the skies above the city back home; motoring with windows down, the air smells like salt, and flowers, and childhood.

Turn left along the water and there is St Helier, the island's capital and my home for the weekend. The seafront is marred by concrete and bunkers, but I realise on arrival that the Radisson has done away with this problem by building its own concrete edifice in front of said front, out on the harbour. The exterior might be the winner of the Carbuncle Cup, but request a sea view and that's exactly what you get: a wall of glass framing the wide expanse of the Bay of St Malo ("We don't say 'the Channel' here," someone later corrects me.)

Inside, all is boutique-calm, crisp and comfortable. Down below, beyond the terrace of the brasserie, slick motor yachts and elegant sailing boats bob about. Next door is a rash of waterfront building works, as others – Marco Pierre White, for one – hurry to tap into the new/old Jersey.

But I'm not here just to stare at the view, as tempting as that is. I have a hectic weekend of relaxation ahead, courtesy of the hotel's package for weekend warriors: two activities, one spa treatment and the Jersey Explorer pass, the latter of which provides free entry into as many of the island's attractions as I can manage. I could rock-climb, I could kayak, abseil or surf. But just at the moment I'm tired, and the weather is looking dodgy at best. I decide on land-sailing for Sunday; it is, the brochure assures me, like all of the "x-treme!" activities on offer here, tailored to vacationing novices. For my first activity, however, I decide that I'm just going to go for a walk.

Walking is a Jersey staple. For an island that only measures nine miles by five, there are an awful lot of roads to ramble. Jersey was way ahead of the environmental zeitgeist in creating a network of "Green Lanes" in 1994. On 50 miles of the island's road network, a 15mph speed limit has been imposed, with priority given to walkers, cyclists and horse riders. In addition, the island boasts 50 miles of coastal paths. Guided treks are scheduled each day of the week, year round – and every spring and autumn, Jersey Tourism puts on a walking festival, running 40-odd trips, including a round-island route.

I choose the Sandy Bays Walk, a regular Saturday afternoon slot on the walking schedule. "Yes, most of my clients are older," says Remi Couriard, my guide, confirming my fears that I appear to be accelerating away from adventure towards a life of sensible shorts and sun hats. But then he starts talking and there is no room left in my brain for such concerns: we walk, and we talk, and walk, and talk some more, down fairy-tale leafy lanes and across wind-blown peninsulas of bracken. The sea is an omnipresent companion, one moment a twinkling promise through the trees, the next a heady blast of islands, rocks and seaspray.

Skirting the southern headland, I ask about the lie of the land. "The island slopes because it is one side of a submerged volcano," explains Remi. He adds – not without a hint of smugness – that Guernsey sits on the other, north-facing slope, which explains "why our temperatures are typically one-and-a-half degrees warmer – and why we can grow potatoes so early". That'll explain why the potatoes cling to such steep fields above the ocean, then, too. They look so precarious and exposed to the elements, but they're actually sheltered? "Oh yes. We plant them right after New Year and the first crop is ready by early spring."

This man is not a potato grower; these are just the sorts of things that a Jersey Blue Badge guide is required to know.

It soon becomes apparent that Remi's knowledge is boundless. He covers a remarkable breadth of topics. He talks about the remains of palaeolithic wild beasts, woolly rhinos and mammoths that are hidden in the depths of a cave on Portelet Common – one of the most important sites of its kind in Europe. He explains the myths of Jersey's dolmens, neolithic burial chambers that are still used ceremonially, apparently, by local pagans. He unravels a system of government with some medieval touches, such as the top man being the Bailiff. He tells how New Jersey got its name: in 1664 the territory west of Manhattan was gifted to the island's Bailiff George de Carteret in exchange for sheltering the young Charles II during his exile. He untangles the tumultuous love life of local lass Lillie Langtry, the "Jersey Lillie": actress, socialite and royal consort. And he recalls the Second World War, when the Channel Islands were the only portion of the British Isles to be occupied by Germany: the Nazis' skills with concrete are demonstrated by the solid command bunker out on Noirmont Point.

Away from the hubbub of St Helier, at times holidaying here feels a little like stumbling into a Famous Five book, what with the shipwrecks and caves and secret German bunkers. It comes as little surprise to discover that Enid Blyton based some stories on a holiday in the Channel Islands.

A company called Jersey Odyssey offers a walk based on nature foraging and camp-craft, which can be extended to an overnighter complete with bivouac building, edible plant collecting and campfire cooking.

I never do make the land-sailing: on the day, rain stops play. Instead, after my surprisingly satisfying walk, I gaze at the sea; enjoy a massage; take in a concert of folksy, home-grown talent. Then I jump on a plane and am home again, feeling as if I've slept for a week.

You know how they say that "a change is as good as a rest"? Perhaps, sometimes, a rest is as good as a rest. Even on an "active" holiday.

Travel essentials: Jersey

Getting there

* The writer flew from Gatwick to Jersey with Flybe (0871 700 2000; flybe.com ), which also flies from 18 other UK airports.

You can also fly on British Airways (0844 493 0787; ba.com ), Jet2 (0871 226 1737; jet2.com ), Manx2 (0871 200 0440; manx2.com ), easyJet (08712 882 236; easyjet.com ), Air France (0871 66 33 777; airfrance.co.uk ), Aurigny (01481 822 886; aurigny.com ), Air Southwest (0870 241 8202; airsouthwest.com ), Bmibaby (0844 245 0055; bmibaby.com ) and Blue Islands (0845 620 2122; blueislands.com ).

* By sea, you can reach Jersey from Portsmouth, Poole and Weymouth on Condor Ferries (01202 207216; condorferries.co.uk).

Staying there

* Radisson Blu Waterfront Hotel, St Helier (01534 671 100; radissonblu.com/hotel-jersey ). Doubles start at £149, including breakfast. The "Active Island" package costs £280 per person; the "Island Discovery" break is £285 per person. Both are based on three-night stays, double occupancy with all breakfasts and one dinner.

More information

* Jersey Tourism: 01534 448800; jersey.com

* Autumn Walking Week: 11-18 September.

* For details of survival walks, contact Jersey Odyssey (01534 498636; jerseyodyssey.co.uk ).