RARELY DOES a street define a city. Yet the Ramblas has come to represent Barcelona, even though it carves a meandering cross-section beyond the medieval walls of the Catalan capital - and many of the locals maintain it has become a tawdry tourist trap. I disagree; it is a magnificent tourist trap.

Spain's second city is rapidly becoming the first choice of travellers on short breaks from Britain. You can fly from any of four London airports, Birmingham or Manchester, and the impending service on Go (0845 60 54321) has reduced return fares to a lowest-ever pounds 80. From the airport, a train runs direct to the Placa de Catalunya, at the top end of the Ramblas.

The Ramblas sets off in the general direction of Bordeaux, a broad stripe separating the old town to the east from the steamy, sordid Barri Xines to the west. The signs read La Rambla; for so salient a street, there is a surprising amount of disagreement on whether the name should be the Spanish plural Las Ramblas, or the Catalan version Les Rambles.

La Rambla seems the accepted compromise, even though the street is made up of five sections, each of them a Rambla.

On a journey from the harbour front to the Placa de Catalunya, you walk along Santa Monica, Caputxins, San Josep, Estudis and Canaletes; were you to continue, you would find a modern pretender (Rambla de Catalunya) protruding north from the Placa. The original name derives from Arabic, but authorities differ on whether it follows from the word "ramla", meaning stream or torrent, or "raml", meaning sand; the unsteady course steered by the one-mile thoroughfare hints that it follows the line of a seasonal waterway.

The first stretch comprises sex shops and flower sellers. Gradually the scenery improves. When the Gran Teatre del Liceu finally re-opens after being gutted in a fire in 1994, it will add some much-needed splendour to the street; meanwhile, the elegant Cafe de l'Opera is the most opulent address.

In Homage to Catalonia, George Orwell wrote evocatively of a Barcelona in the throes of devastation in the Spanish Civil War, and described violent gun battles in the Ramblas. Bullet holes still perforate the fabric of some of the buildings, but Orwell would barely recognise the street today: as well as noise, dust, dirt and fumes, you find McDonald's and Burger King (doble Whopper completo, pounds 4). As the place where most of Barcelona's tourists converge, the Ramblas sees a phenomenal amount of street crime; carry nothing more valuable than a throwaway camera.

The Sant Josep (or Boqueria) market, just beyond the halfway point, is a frenzy of commerce housed within a grand building showing modernista flourishes. The noise of humanity and traffic is augmented by the squawk of a thousand parrots, unhappily caged for sale.

The final stretch before the square is the Rambla de Canaletes, named for the Font de Canaletes. Drink from this iron fountain, and according to whichever local legend you believe you are (a) certain to return, (b) will never actually leave, or (c) become an honorary citizen of Barcelona.

The Ramblas unloads its cargo of tourists and ruffians into Placa de Catalunya, the size of Trafalgar Square. On the north-east side, the ninth-floor cafe of El Corte Ingles presents a splendid view of the city. But you may just think you have seen it all.