I’m sitting in a blood-warm hot-tub on a jetty sticking out from a tiny Swedish island sinking champagne and shoals of oysters – so comfortable that I could wallow in this balmy security for ever. But no.

“Now you must go in the sea,” instructs Camilla, my hostess. The sea, Camilla? The sea just now is 10C (50F). But there’s no argument, so out I get, pausing above the diamond-tipped waves for one teetering moment ... before lowering myself, inch by inch into the bitter tide, squealing all the way like a piglet.

There is something astonishingly refreshing about life on the west coast of Sweden. It’s not just the bracing oyster-bar rituals available on the gaunt island of Käringön, an hour north of Gothenburg. It lies, more acutely, in the unspoilt landscape, the close, intimate, human, small-scale communities that dot this Bohuslän coast. Cosy is the word.

I was on my way north up the E6, heading for the Nordic Oyster Opening Championships, which sounds like a joke, but is, in fact, exactly the kind of festival that matters around here. Every April in the fishing town of Grebbestad, oyster-boffs from Denmark, Finland, Norway, Iceland and Sweden gather to compete for seafood glory in a kind of Crustacean Olympics. It’s so Scandinavian, so indicative of this seagoing region, which fulfils a full 90 per cent of the nation’s oyster appetite. You don’t, though, need to go to the festival to appreciate the fantastic seafood. There are oyster activities all summer and a highlight is the Gothenburg Cultural Festival in August.

I flew to Gothenburg first, strolling the wide boulevards of this attractively small city, discovering that my guidebook claims were pretty accurate – people seem more open here than elsewhere in Sweden, perhaps influenced by the jolly Danes just down the ocean road.

There are 656 restaurants in the city, four with Michelin stars, in one of which I met Leif Mannerström, a cook so famous that his face adorns a Swedish postage stamp – a man who counts Bono, Mick Jagger and John Cleese among clients at his restaurant Sjömagasinet, down on the waterfront in a crisscross of antique beams. In Britain, a chef like this would be pure rock’n’roll. In Sweden?

What did he make, say, of Gordon Ramsay’s hellish verbal antics? “Terrible,” Leif said, shaking his postage-stamp head. “My belief is you have to be very nice to people.” See? I was to meet Leif later, up in Grebbestad, where he was scheduled to judge the oyster contest. Meanwhile, I jumped into a Volvo (naturally), and mooched off ahead.

The E6 rumbles through rolling countryside, but the real landscape joy lies 30 minutes away on the coast, where fishing villages and ferry-linked islands speckle the seashore like film sets built for the kind of movie that employs moody silences and vast panoramas (Ingrid Bergman lived locally, as it happens).

Think of the frilliest doily you’ve ever seen and cast it in stone – that’s west Sweden, all squiggles and chunky bits. In July, Swedes flock here to wolf fish or take ferries out to the islands to sunbathe and stroll. For the rest of the year the coast is clear, the air fresh, and the sea crystal, if sometimes chilly.

Karingo Oyster Bar on Käringön Island, 30 minutes’ ferry ride away, provided the clearest glimpse of local life – Camilla and her dad running their upmarket little oyster-and-tub business as a strictly family concern, refusing large groups and defiantly shutting during high summer because seasonal tourism jars with their cooler ethos. Would that happen in many countries? Probably not.

Finally I came to Grebbestad itself, typical of all these coastal villages, a parade of brightly coloured wooden houses rising in a pristine blaze from an exquisite fjord-harbour, streets neat with decorous charm and silent courtesy. At Greby’s, a rambling harbourside restaurant where the oyster contest was taking place, they found escape from their own reserve.

Outside, all was tranquil. Inside, a blonde with a mike was shouting at 200 mild, but cheery, seafood enthusiasts as 20 oystermen psyched themselves up for crustacean wars, sinking beer and cradling wicked knives. Speakers boomed the strains of Chariots of Fire. I had found the Swedish soul at play.

Diving in, I bumped into Michael Moran, reigning world champion oyster-opener, flown in from Ireland to demonstrate his peculiar magic. He told me that his secret was a pint of something before the off – but the local lads were ahead of him, as was the audience, though no one was ever less than courteous.

Someone shouted “Whooee!” and many waved flags. Competing Swedes, Norwegians, Danes, Icelanders and Finns grabbed knives . . . and the competition began.

An amazing day we had. The skills were extraordinary, contestants slicing 30 oysters in three minutes tops, though there were time defaults if you cut the meat – which is how I met chef Leif Mannerström again, judging the rounds, pointing to the shells shaking his sorry head, saying: “It’s cut, it’s cut ...”

On stage under bright lights, faces became pictures of intensity. This was not tourist play-acting, but a community exploring its own talents without a shred of irony. You could feel the goodwill. Fresh music boomed with each new contestant. Rocky, We will Rock You ... The audience “Whooeed!” Outside, just silence, intensely sweet.

I nipped out to grab lunch, climb a hill, look around; took a boat ride to the wild oyster-beds just offshore – tourists can do that – and met two divers hauling up their ocean gold. They made me laugh with stories of how they wanted to be doing this on Zimmer frames as old men, never mind sub-zero winter temperatures. Now that’s Swedish cool.

Back at Greby’s, stallholders were handing out local lobster, herring and crispbread as the competition grew frantic.

A Swede won in the end, thank heavens, spraying the crowd with champagne like a racing driver, emphasising the fact that this was more than a laugh. It was a demonstration of what’s important here, a tough-handed reflection of ocean economy, small-town courtesy, Swedish fun.

That night, in nearby Tanumshede, I had a lovely meal at Tanums Gestgifveri – oysters, of course. Driving back next morning I could hardly believe the intensity of the day before. But it had been real enough, in a way that things rarely are.

Need to know

Nicholas Roe travelled with the West Sweden Tourist Board (www.west-sweden.com), Gothenburg & Co (www.gothenburg.com) and Scandinavian Airlines (0870 60727727, www.flysas.co.uk ), which flies from Heathrow to Gothenburg from £108 return. Simply Sweden (0845 8900300, www. simplysweden.co.uk) offers a three-night Oyster Safari, including a visit to the Karingo Oyster Bar, from £982pp, including flights.

Restaurants: Sjömagasinet (00 46 31 775 5920, www.sjomagasinet.se ); Tanums Gestgifveri (5 252 9010, www. tanumsgestgifveri.com ); Karingo Oyster Bar (www.karingo.com ).

Festivals: Nordic Oyster Opening Championship April 19, 2008 (details from www.west-sweden.com). The Gothenburg Cultural Festival is from August 14-19 and includes open-air restaurants serving oysters.

Further information: Swedish Tourist Board (0207-108 6168, www.visitsweden.com).

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