I was walking along Barcelona's Carrer del Consell de Cent, a street just a few blocks above the human rush of La Rambla, when I heard the sneeze.

It was a magnificent sneeze, operatic and full-bodied. First came a dramatic drawing-in of breath, like a Teutonic declaration of regret. Then a pregnant silence during which time seemed to stop . . . and then finally the explosion, a throaty holler carrying breath from the belly, the gut, the entire body from sinus to heel. It was a sneeze that could christen a ship, or launch a space shuttle, or start a war.

I wasn't the only person on the street to stop and look up in admiration, or maybe it was fear. There on a balcony of an apartment house stood the perpetrator, a small, cleanshaven man with his hair brushed back. He was perched at the railing, elbows locked, a small but unmistakable smile on his face. What splendid havoc he had wrought! He did not look embarrassed, or even crazy. He looked like a man quietly pleased that he had completed some small household task.

Whenever I think of my visit to Barcelona I think of that sneeze. High drama in small actions. Excess in daily battle with restraint. A rush of physical energy, spontaneous public performance, strange creativity, civic engagement and the ability to surprise and delight with nothing more than what the gods have granted . . . it's all there in that sneeze, and in Barcelona too.

Going to Barcelona to visit Spain is like going to San Francisco to visit the United States. Both are hauntingly beautiful waterfront cities, full of intriguing neighborhoods, layers of historical charm, cozy cafes populated by cheerful nonconformists and incredible food, all of it sustained by a comfortable business class that keeps money coursing along the streets. Both cities have rich histories of radical politics. And both places define themselves largely by their differences from the motherland rather than their connections to it, fundamentally imagining themselves nations apart. Both cities earn and return contempt from their more conservative countrymen.

Of course, San Francisco was never the capital of its own thriving city-state, and it has never (at least not yet) been stormed by a fascist military led by a fellow who called himself Generalissimo and quashed its language, art and culture for more than 30 years, as Barcelona was from the time of the Spanish Civil War until 1975, when Francisco Franco died. So let's not take that comparison any further. But let's stipulate that Barcelona is in Spain but not of Spain, more a regionally distinctive and independent-minded Mediterranean port city than an outpost of Madrid.

More than half of the Barcelonese speak Catalan, an ancient regional language derived from Latin, French and local influences (and not, they insist, a mere dialect of Castillian Spanish). The locals don't share the Spanish obsessions of bullfights and flamenco. The city has a long history, first as a walled Roman outpost, then as a minor colonial power itself, and then, for ages, as proud victim of the expanding power of a centralized Spanish nation based in Madrid. Its politics have tended to extremes--anarchism and communism, usually in pitched battle with the conservatism of the bourgeoisie, who have prospered in the area's strong trade, banking, textile and retail businesses. Barcelona is an incubator of radical art--modernist Joan Miro is a local hero, Salvador Dali held forth in a nearby town, Picasso endured his blue period here and a group of architects who sought to defy the great European traditions blossomed in Barcelona about 100 years ago, in one of the continent's memorable flowerings of regional creativity.

You can see Barcelona's differ-ences everywhere. Along the city's legendary promenade, La Rambla, men charge for the privilege of sitting in chairs they do not seem to own, roosters are for sale in cages next to parrots and beggars appear with leashfuls of dogs. One local ceremony is a death-defying stunt in which young local men build a human tower as high as 70 feet. The high-design broadcast tower that hugs the harborside hill of Montjuic protrudes from the slope like a giant canape. The home-grown creative genius, the modernist visionary architect Antoni Gaudi, whose work is all around the city, is derided by the nation's classicists as a kind of crazy uncle with a building permit. His greatest work, and the city's signature monument, is the unfinished Sagrada Familia church. It looms over the city like a glue sniffer's vision of Purgatory, its fantastic fingers reaching for God.

One night at Txapela, a superb Basque-style tapas bar on the grand Passeig de Gracia, an older, presumably homeless woman created a ruckus by pounding together a pair of cleaning brushes wrapped in newspaper and duct tape. At first I thought she'd continue down the street, but she stopped right in front of the sidewalk tables and pounded the brushes together all night long. A small box for coins lay at her feet. It's said that the people at the margins of a culture often define it best, and this woman, like the sneezer, was very Barcelonese: a performer, a merchant, resourceful, odd and hard to ignore. I am what I am but here I am, she seemed to say, and that could be Barcelona's slogan, too.

Everybody who comes to Barcelona finds themselves on La Rambla, the former drainage ditch turned municipal centerpiece that teems with stalls of flowers and birds, cafes and sidewalk artists, living sculptures and hack musicians, at least one of whom rolls a full-size upright piano up and down the half-mile promenade and belts out American pop songs from the '70s wherever a crowd is gathered. Vehicular traffic is routed into two lanes along the edges, creating a broad central walkway framed by an arch of plane trees.

What sets La Rambla apart from the manufactured tourist gantlets in the United States is that La Rambla was a civic gathering place long before tourism set in. La Rambla runs from the waterfront statue of (another local hero of sorts) Christopher Columbus, through the old parts of town that date from the 14th century, and terminates at the Placa de Catalunya, a park with lawns and fountains that forms the gateway into the city's urbane 19th-century extension known as L'Eixample. During my visit, a building facing the square marking the end of La Rambla was draped with a four-story, black-and-white close-up of a young girl looking directly at the passers-by. A slogan in Catalan seemed to solicit help for the poor. Someone had climbed the scaffolding and painted bloody tears streaming down her face. The red paint trickled off the poster, onto the scaffolding, and was splashed in wide bloody puddles on the sidewalk.

Many of the people on La Rambla are of course visitors--mostly Europeans, families and couples and young people with tattoos and colored hair and, increasingly, patrons of the cruise ships that dock at the waterfront and disgorge their waddling thousands like livestock wearing T-shirts and fanny packs. But the locals are there too: An 1840s marketplace called Mercat de la Bouqueria is right on La Rambla, and it remains the city's main produce mart. Its stalls still sell sheep's brains, bull tripe and other regional specialties to householders who live nearby. It's loaded with dried fruit and a bewildering array of olives, and fish the size of small hogs, split open and bloody and hanging from hooks.

There were many Barcelonese out on La Rambla all day: older merchants walking slowly beneath halos of gray; La Rambla's signature "living statues" on break, smoking idly in their metallic outfits and body paint and flirting with visitors; and a surprising number of Barcelona's best on parade. The city has come through the '90s a prosperous, robust Mediterranean port city, and in the early evening La Rambla fills with the city's almost impossibly beautiful, Euro-chic yuppies--the women in sleek skirts slit to the thigh and form-fitting dresses, the men in sharp woolen three-button suits, their collars open at the throat. As a cab driver reported with fetching specificity, Barcelona is the "fourth most important" center of European fashion--after Paris, London and Milan--and from appearances, nobody would argue.

If you pay close attention on La Rambla, there are sites and scenes that open windows into the city's character, making the promenade a great tourist sampler. In front of the market you'll find a sidewalk mosaic by Joan Miro. Just off La Rambla is Placa Reial, a courtyard ringed with restaurants and shops that attracts a gleeful mix of arrivistes, backpackers and ne'er-do-wells who seem to be stoned. The iron street lamps were designed by the young Gaudi--I watched as some local kids playing soccer pinged a goal-kick right off a lamp's delicately filigreed base. It's said that Dali, in town from his nearby native village of Figueres, would come here to a pet store on the placio to buy his ever-fascinating ants.

Just a block off La Rambla in the other direction is one of many Gaudi buildings, Palau Guell, an early work in which most of the extravagance is found in the house's decorative metalwork and the indulgent indoor courtyards. That handsome house, now a theater museum, is on the fringe of Barri Xines (the "Chinese" or foreign quarter; Barcelona has a long tradition of xenophobia), the city's area of ill repute. One afternoon, on a misdirected mission to the seafront's popular overhead tram, my wife and I detoured through Barri Xines. It was siesta time, and though Barcelona does not observe this ritual as closely as other parts of Spain, many shops were closed, their graffiti'd metal doors pulled down tight. As we walked the narrow, stinking streets we encountered a group of three young men, all wearing black and looking as unfriendly as anybody I saw during our visit. One of them made an elaborate gesture below the belt. I confess to vast ignorance about international obscene gestures, but I'm pretty sure it was a threat or a slur. We kept on going and stayed out of Barri Xines for the rest of our stay.

On the other side of La Rambla you'll find the Barri Gotic, the ancient Gothic quarter that is filled with hotels, shops, private homes, youth hostels and restaurants. No wider than most alleys in the United States, the streets offer a fun and safe blunder; you can easily spend a day visiting Placa del Rei (on the top step of which, it is said, Isabella and Ferdinand greeted the returning Columbus), or vainly trying to follow the fragments of the city's early walls, dating from the 4th-century Romans, or touring the grand cathedral, a bit gloomy on the outside by day but a knockout at night. Its earliest parts date from 1298--some of the altars are stunningly morose--and its inside spaces are vast and streaked with centuries of soot.

Although Barcelona has a long and often painful political history, it's no radical hotbed today. The only overtly political act I observed was one sunny afternoon near Palau de la Generalitat, the headquarters of Catalonian government, where Barcelona's doctors and medical staff were having a demonstration. They were in high spirits and seemed to be agitating for more money for health care. The scooter police looked bored.

Aside from that, I didn't see anything suggesting a drive for political independence from Madrid, historically a divisive issue in Barcelona. In fact, local elections were coming up, and the streets were lined with giant posters of the candidates' faces. Most appeared to be genial technocrats of indistinct nationality, making claims for a role for Barcelona in the rising tide of European unity. One of them looked like your friendly uncle, the rich bald lawyer who dresses so well.

But when I took a train ride two hours outside Barcelona to one of the smaller, shabbier towns in the Catalonian countryside, things felt very different. I saw lots of ripe graffiti about independence and overthrow. I saw a lot of people hanging around the streets who did not appear to have any place to go. It's clear that the prosperity of Barcelona has not spread widely into the countryside (unemployment in Spain is reportedly 16 percent). Much of the graffiti used the word llibre, which I took to be Catalan for freedom. The only time I saw that word in Barcelona was on signs outside parking lots to announce the availability of spaces.

And that sums things up pretty well. In the poorer countryside, people want political change. In well-to-do Barcelona, they want more parking.

Salvador Dali once said that "the genius of Gaudi is that he had no taste." Of course, one is tempted to consider the source, as they say. But one of the best ways to tour Barcelona is to test out Dali's thesis for yourself. Visiting Gaudi's buildings not only lets you contemplate that age-old question--Is It Art, or Is It Just an Untreated Personality Disorder?--but it steers you into the city's most interesting neighborhoods.

The best place to start is on Passeig de Gracia, one of the great boulevards of Europe. About eight blocks up you'll find Casa Mila, an apartment house that sweeps around the street corner and whose color and lines suggest, to me, human bone (others see a rock quarry). The balconies, rippling with organic ironwork, undulate across the surface. The whole things squats on cavelike archways at the street.

Inside, on the top floor, in the midst of the building's striking futuro-Gothic attic, is a small museum called Espai Gaudi. Using very little language and well-selected images, the exhibits provide a useful overview: Gaudi's early works, rich in Gothic, Moorish and other influences and reflecting his youthful desire to create a neo-Catalonian aesthetic; his later works, in which he pursues a more organic, decorative style suggesting both French art nouveau and Frank Lloyd Wright; and finally his end-of-life obsession, the Sagrada Familia church, a monumental and utterly idiosyncratic expression. Gaudi liberally covered his work with trencadis, broken-glass mosaics that add a playful, modern twist to the longstanding Iberian taste for tilework.

Out on the roof of Casa Mila there are sculptural towers and stairwells, all covered with trencadis. In the shapes some visitors see armored warriors, others witches, still others ice cream cones or mushrooms. On weekend evenings drinks are served on the roof, and that's got to be one of the great outposts for viewing Barcelona. Like the psychedelic art of the '60s in America, much of Gaudi's work improves when viewed while under the influence.

Ultimately you'll wind up at Sagrada Familia. Gaudi's church, still unfinished, is a tribute to St. Joseph--taken by some as a symbol in struggle to unite workers and owners, and long a major figure in Barcelonese cosmology. From a distance the church seems to pierce the low-lying Eixample, its bell towers like Jules Verne missiles with glinting mosaic payloads.

It only gets stranger as you approach. The Facade of the Glory, where most visitors enter, is downright scary. The main figure is Jesus, his body slack and suspended from a crossed pair of I-beams. Below, in the middle of a set of figures interpreting the Denial of Peter, appears a flat disc with an etched portrait of Jesus in agony, rendered in a highly modern outline style. Below that, between the two main doors, stands Jesus on the column, bereft and beyond hope and depicted in angular modern abstraction by Josep Maria Subirachs. All around are turtles, snakes, lizards and vivid episodes from the Bible. Behind them Evil itself, in the form of half-realized protuberances, seems to be materializing from the atmosphere.

Though right-wing thugs busted up this rising monument to Catalonian spirit in 1936, serious work was taken up again in the mid-'50s. And since that time the Barcelonese (and several Japanese patrons) have embraced this strange and irresistible creation and kept it going. Purists chafe that Gaudi's vision is being tampered with, reduced by lesser minds and craftsmen. But a more generous view is that the evolving work is now more of the city and its residents, if less of the man.

When you go, pay for the four-story elevator ride, which takes you to a nautilus staircase that crawls up the length of one bell tower. Keep walking upward until the stairs spill you out to a small balcony, and take a look at the city. From high atop this strangely beautiful tower to Heaven, amid the mosaic inlays and godly visions in stone, the wind from the Mediterranean whistling around this curious spike of geometry, all of Barcelona spreads out below you.

And if you find you need to sneeze, by all means go right ahead. Barcelona is not a place to hold back.

DETAILS: Barcelona

GETTING THERE: We booked air and hotels through Spain Plus (703-522-4449), an offshoot of Bargain Airfares, an Arlington-based air fare consolidator. Spain Plus specializes in discount air-and-hotel packages to Spain. We spent four nights in Barcelona, two in Seville and one in Madrid. Our package included round-trip Spanair flights to Barcelona (connecting in Madrid), an Air Europa flight from Barcelona to Seville and a first-class AVE (new, high-speed) train trip from Seville to Madrid. For air, seven nights of hotel including breakfast, plus the train tickets, we paid $1,200 per person, double occupancy. Although our hotel in Seville (the Inglaterre) was disappointing, otherwise we felt we received very good value at this price.

Booking direct through Spanair, sale fares for fall travel, with a connection in Madrid, range from $393 to $469 from Dulles. The best quote we could find from BWI and Reagan National was $567 on Delta, via New York.

WHERE TO STAY: Spain Plus put us in Hotel Regente (Rambla Catalunya 76; 011-34-93-487-5989, rates from around $150), a small place just beyond La Rambla and near some of Barcelona's best shopping, eating and walking. The highlight of our small but clean and stylish room was an Astroturf-covered balcony that overlooked the low-rise cityscape. I'd recommend staying in urbane L'Eixample rather than along La Rambla or in the Barri Gotic, unless you want to be right in the midst of the crowds.

WHAT TO DO: In a city full of museums, historic buildings and cultural attractions, I'd recommend the following three clusters of activities; each could easily consume a day.

* Waterfront/Barceloneta/Parc de la Ciutadella. Stroll the Mediterranean beach, make quick work of the formerly charming, increasingly cruise-passenger-bait neighborhood of Barceloneta and head for the Parc, a civic garden highlit by Museu d'Art Modern. If you're not acrophobic, take the overhead tram from Barceloneta across the water to Montjuic (highlight: Fundacio Miro, with a great collection of local modernist works) and Palau Nacional, home to Museu Nacional d'Art de Catalun- ya, perhaps the best place to explore the region's distinctive, pan-Mediterranean culture.

* La Rambla. Spend the day walking from the Columbus Statue all the way to Placa de Catalunya, permitting yourself to drift into Barri Gotic, the Gothic Quarter. Take a break at Placa Reial, an arty, funky old courtyard featuring original Gaudi lampposts. Any guidebook can tell you what to look for on La Rambla, but make sure you visit Mercat de la Boqueria, an old market, and don't try to take a serious meal at on-La-Rambla restaurants. The paella tastes like the stuff your mother called "Spanish rice." The other not-to-miss in Barri Gotic: The gloomy, sooty Catedral, built mostly from 1298 to 1430.

* The Gaudi Tour. Again walking up the beautiful Passeig de Gracia, about eight blocks above La Rambla you'll find La Pedrera (a k a Casa Mila), a beautiful example of the Gaudi style and home to an attic museum called Espai Gaudi. From there you can walk (or cab) to Sagrada Familia, the other Gaudi must-see. After seeing these two you'll know if you need any more of Gaudi. But even if you don't, you might want to cab to Parc Guell, a civic garden that's a riot of Gaudian indiscretion but, more important, a good excuse to get into residential Barcelona, away from the tourist crush.

READING: No guidebook is better than another; just make sure yours was published after '95, so it includes the civic assets and liabilities created by the '92 Olympics. For good, deep background, read Robert Hughes's "Barcelona" (Vintage), a deeply researched and wildly opinionated view of the city and its history.

INFORMATION: Tourist Office of Spain, 1-888-657-7246 (brochure only) or 212-265-8822, www.okspain.org or www.spaintour.com.--Craig Stoltz