WALK DOWN the pedestrianised lane in London W1 that links Beak Street with Great Marlborough Street, and there is nothing to remind you that this was once the most fashionable street in the trendiest city in the whole world.

Nothing, that is, apart from the signs nearby pointing you towards "Carnaby", and the archways at each end, announcing the entrance to Carnaby Street, west Soho - an area that would, in more stylish times, surely have been renamed Woho.

Carnaby Street once epitomised Swinging London; it was more a design phenomenon than an architectural statement. During the 1960s, brash, bright colours and psychedelic patterns screamed out from every building; boutiques sold the latest fads and trends, and every dedicated follower of fashion wanted to be there.

Until the late 1950s, it was a quiet backwater, unremarkable, lined mainly with tobacconists' shops. Then an entrepreneur called John Stephen bought his first boutique there and began selling a type of fashionable men's clothing that had never been seen before, and the street began to change. In 1960, Michael Davies, a graphic designer who had trained at the RCA, decorated the outside of Domino Male. Lord John became a fixture on the corner of Ganton Street. By 1966, when Time magazine famously featured Swinging London on its cover, John Stephen owned 10 boutiques in Carnaby Street, and anyone who gave any thought at all to what they looked like wanted to be seen there. But international recognition marked the beginning of the street's decline; trends changed, the cool people went elsewhere, and Carnaby Street was never the same again.

There are still boutiques there, of course, many of them catering to groups of tourists on their way from Liberty's to the more interesting parts of Soho. The only psychedelic decor these days is the front of a boutique called Heaven. But when you get inside, although there are plenty of cheesecloth shirts and ethnic jewellery, the best-selling lines appear to be tins of English tea and models of red London buses displayed in the souvenir department at the back.

The people who bought their Union Jack clothes in Carnaby Street in the Sixties are older now; if they ever come back, they might be tempted by the Pringle sweaters in the shop on the corner of Foubert's Place. Boots the Chemist is there, too, in a prominent site halfway up the street; Whittard Teas is on another corner, and there's a nice candle shop nearby. The nearest you get to bright colour is in Octopus, a jewellery shop which is currently displaying orange and turquoise Michelin tyres in its window displays.

If you believe the publicity, end-of-the-century Carnaby is not so much a street, more a happening district. You can even visit it on the web (at: www.streetsensation.co.uk). This technological enhancement excepted, Carnaby Street is rooted in a version of the past.

After "the look" faded from popularity, the fashion turned to flower power. They still have it in London W1, but nowadays, it is strictly confined to the geraniums and petunias found in the corporation hanging baskets.