Barcelona: Guide for Olympic Visitors : The highs and lows of Spain’s Mediterranean metropolis, from Antoni Gaudi to <i> tapas</i> bars.

With the Summer Olympics set to begin in less than two weeks (July 25), the world spotlight will soon be on this Mediterranean city. For those who are heading to the Games--or anyone planning on visiting Barcelona soon--here are some useful tips.

WHAT TO SEE Barcelona is a city best experienced by wandering on foot, although its world-class museums, historic monuments and innovative architecture are anything but pedestrian.

At the heart of the city is Las Ramblas, a leafy, tree-lined promenade that runs from the harbor to Placa de Catalunya. It’s the place in town to stroll, and is lined with flower stalls, craft-sellers and colorful newsstands so big that they verge on being bookstores.

At the foot of the Ramblas is the waterfront, newly renovated as part of an Olympian face lift for the Games. Just west of Las Ramblas, near the harbor, is Barcelona’s red-light district, the so-called Barrio Chino. Go softly there by day, and go not at all after dark.

The Barri Gotic, east of Las Ramblas, is the historic center of medieval Barcelona. Weaving between massive Roman walls and ornate palaces, cobbled lanes take the visitor back through the ages.

The area boasts some of the city’s most famous historic monuments, including the pseudo-Gothic Barcelona Cathedral and the 15th-Century Government Palace. Several important museums are also in or near this district, including one dedicated exclusively to the work of Pablo Picasso.

Saturdays at 4 p.m. and Sundays at noon, traditionalists young and old gather in front of the cathedral for the sardana , the dance that celebrates Catalonian nationhood. Joining hands to form intimate circles, dancers sway in delicate unison to the measured music of a small orchestra.

For visitors who will not have time to travel outside of Barcelona, the Poble Espanyol, near the Olympic Stadium, offers a taste of Spain at large. Built for the 1929 World’s Fair, this model village attempts to re-create the diversity of Spain.

MUSEUMS The Picasso Museum, at 15 Carrer de Montcada, is dedicated solely to the work of artist Pablo Picasso. It’s only one of more than 40 museums in Barcelona.

On the Montjuic, near the Olympic Stadium and other sports facilities, is the Joan Miro Foundation, housing a collection of that Catalan surrealist’s varied works.

A third important art museum is the Antoni Tapies Foundation, at 255 Carrer d’Arago, featuring the art of the contemporary Catalan artist.

Other museums are variously dedicated to ships, perfume, shoemaking and holograms, to name a few. The Maritime Museum, near the harbor-side Columbus monument, is especially worth a stop.

A complete listing of museums and their hours of operation is available from the Barcelona tourism office at 658 Gran Via de les Corts Catalanes, local phone 301-7443.

ARCHITECTURE To look at one of Antoni Gaudi’s curvaceous, audaciously colorful buildings is to realize how utterly conventional most other structures are.

A modernist to the extreme, the Catalan architect created a number of monuments to the imagination in Barcelona before he was killed by a streetcar in 1926.

What some consider his most spectacular work, La Sagrada Familia, is a soaring skeleton of a cathedral whose cornerstone was laid in 1884. Still under construction, the cathedral is not scheduled for completion until well into the next century. Spiral staircases snake through its completed stone towers, the tops of which are covered in fanciful tile mosaics. The view of the city from the towers is well worth the climb, or the nominal charge for an elevator ride.

Another Gaudi work is Parc Guell, a green, tree-filled enclave whose fairyland buildings, fountains and landscaping attract tourists and natives alike. Like the Sagrada Familia in the distance, the park offers visitors a great view of the city and blue Mediterranean beyond.

Detailed guides to the work of Gaudi and other modernist architects are available at newsstands and bookstores throughout the city.

NIGHT LIFE The beautiful people in Barcelona don’t get going until well past midnight, and on weekends they rock on past dawn. Spaniards may visit several bars and clubs over the course of a night, never lingering for more than a drink or two in any.

Doormen with an eye for tourists may exact cover charges arbitrarily; the best way to avoid this is to dress sharp and look like you know where you’re going. Sometimes, however, cover charges are unavoidable. Be aware that mixed drinks in trendy clubs often cost $10 and up.

The following are some suggestions for a variety of tastes:

Up and Down is a dressy restaurant upstairs and hip disco downstairs. Jackets are required for men. Numancia, 179.

San Francisco is a more casual disco with a younger crowd. Consell de Cent, 213.

Apolo is a late-night stop for those who really like to dance. Late means 4 a.m. or after. A converted theater, this club attracts both gay and straight patrons. The neighborhood can be rough, however. Nou de la Rambla, 113.

Torres de Avila is a unusual bar that is definitely worth a visit, if only to look around (there is no dancng). Designed by Javier Mariscal, creator of the official Olympic mascot, Cobi, this bizarre nightspot features an indoor revolving star-scape, round pool table and rooftop terrace with a great view of the city. It is right on Montjuic, within walking distance of the Olympic Stadium. Marques de Comillas, in the Poble Espanyol.

La Pira is a converted amusement park, and while there is no dancing, its patrons can drink while sitting in bumper cars and other former carnival rides. Sometimes a younger crowd. Provenca 171.

La Paloma, open since 1903, is the place to go in Barcelona for ballroom dancing to the music of a live orchestra. It is open Thursday through Sunday nights for two sessions: 6-8:30 p.m. and 11:30 p.m.-3:30 a.m. Tigre 27.

Flamenco dancers perform after 11 p.m. at El Tablau de Carmen. Since flamenco is not native to Catalonia, El Tablau de Carmen caters largely to tourists. Arcs 9, in the Poble Espanyol.

For more details on entertainment offerings, consult the weekly Guia del Ocio, available at newsstands. It comes out every Thursday.

MONEY The Spanish unit of currency is the peseta. You’ll probably get a bit less, but a good rule of thumb when converting U.S. dollars to Spanish pesetas is to figure that there are about 100 pesetas to the dollar. When spending pesetas, divide a given price by 100: green 1,000-peseta notes are worth about $10, red 2,000-peseta notes about $20 and purple 5,000-peseta notes are worth about $50. Expect all colors to vanish with dismaying speed: Spain has become an expensive country over the past decade, and Barcelona especially so during the Games.

Good hotels will change money for their guests, but sometimes charge a hefty commission. In Barcelona, several commercial money-changing services have highly visible offices along Las Ramblas and in other tourist areas. Most do not charge a commission but make up for it by offering lower exchange rates. Conveniently, however, these are open seven days a week, some until midnight. Overall, banks are usually the best places to change money.

To avoid carrying large amounts of cash, charge goods and services on a credit card. They are widely accepted and generally hassle-free.

Spanish coins can be confusing because there are both old and new coins in circulation--different sizes for the same denominations. Look carefully at the number on the coin to determine its value. A pocketful of change can be worth a lot in Spain: there is a 100-peseta coin, a 200-peseta coin and a 500-peseta coin, worth about $1, $2 and $5, respectively.

TIPPING Many restaurants, especially better ones, automatically add a service charge of 15%-20% to the bill. Look on the menu to see if this is included. If it is not, tipping this amount is suggested--if you liked the service.

In less formal establishments such as bars and cafes, tips are generally not expected, though it is customary to leave some change for the waiter or barman.

Tips to others--tour guides, taxi drivers and hotel staff--should be awarded depending on your level of satisfaction with the service provided. In general, Spaniards don’t tip as much or as often as Americans.

TRANSPORTATION Traffic in Barcelona is often terrible, despite the new beltway around the city. With sections of the city closed off to private vehicles during the Games, making use of Barcelona’s cheap, efficient public transportation is highly recommended.

When the flag drops in one of Barcelona’s 11,000 black-and-yellow taxis, it costs 250 pesetas. Fares are calculated automatically per meter according to time and distance traveled.

There is a 300-peseta surcharge for trips to and from the airport, and a 100-peseta surcharge per suitcase. Additional charges may be exacted for nighttime and weekend trips. If you bring your dog, that will cost 125 pesetas extra. Despite these surcharges, drivers seem basically honest and the taxis are generally reasonable in cost. If in doubt, ask for an itemized receipt.

During the Games, a special transportation pass valid on the city’s public transportation system will be available for 3,000 pesetas, about $30. It can be purchased at any subway station. Barcelona’s subway--the Metro--is one of the fastest and easiest ways to get around. Safe and reasonably clean, the Metro is also one of the city’s few bargains. A single-trip ticket costs 90 pesetas; a 10-trip ticket for 460 pesetas is especially economical. These can be purchased from machines in any Metro station or from the station attendants in glass ticket booths. Metro maps, available from the attendants, are free.

The 10-trip ticket has a magnetic strip on the back. To use it, slide the ticket into the designated slot on the left-hand side of the turnstile, re-collect it and pass through. Don’t be confused by the yellow ticket-validating machine also present at turnstiles: This is for use with joint bus-Metro tickets.

The Metro operates from 5 a.m. until 11 p.m. Monday through Friday, and until 1 a.m. on Saturday and Sunday mornings. Stations are identified by signs featuring a blue “M” inside a red diamond.

The city bus system is also convenient, but is hostage to traffic. Single trips cost 90 or 100 pesetas, depending on the time of day or night. A 10-trip ticket is 510 pesetas. Free maps are available from attendants at Metro stations. For more information about public transportation, call locally 412-0000.

PERSONAL SAFETY Barcelona, like the rest of Spain, is relatively free from violent crime. There are, however, pickpockets and purse-snatchers in abundance. Purses should be worn across the body, and wallets carried in secure pockets. Don’t carry large amounts of cash.

“Visitors should take the same precautions they take in New York or any other big city in the U.S.,” said Clyde Howard, chief of the consular section at the U.S. Consulate in Barcelona.

Should an incident occur, the following telephone numbers may be useful: police, 091; medical emergency, 061; fire, 080. The U.S. Consulate is at Reina Elisenda, 23-25. From July 20 to Aug. 14, the Consulate will be open from 8:30 a.m. to 8 p.m., Monday through Friday, and on Saturdays from 9 a.m. to 1 p.m.

FOOD Over the centuries, Catalan cuisine has had a variety of cultural influences, from Romans to Moors to Italian merchants bearing spices from the Far East. Seafood is a regional specialty.

But like food throughout Spain, Catalan cooking tends to be heavy on olive oil and highly caloric. Don’t be put off by appearances--many dishes that look unappetizing are really quite tasty.

Tapas are essentially hors d’oeuvres, and they often constitute a meal for Spaniards. Ranging from stuffed mushrooms to deep-fried squid, they are usually consumed while standing at the bar. Most bars display a selection in a glass case, and pointing is generally an easy and effective way of ordering. For best results, ask which is the house specialty.

Another Spanish favorite is the bocadillo , or sandwich. Made with crusty bread and a variety of flavorful ingredients, they are cheap and good, though sometimes a little dry.

Mealtimes may seem late to Americans: Lunch is usually eaten about 2 p.m., and supper after 10 p.m.

The water is safe to drink everywhere in Spain, although mineral water is popular and readily available in all restaurants, bars and cafeterias .

Cafeterias --informal cafes that take their name from the fact that they serve coffee--can be found on practically any street. Many offer a menu del dia , or menu of the day, for lunch. This is usually a three-course meal costing between 700 and 1,500 pesetas. Otherwise, most dining is a la carte.

Quintessentially Spanish, cafe con leche is strong, espresso-like coffee made with steamed milk. It is available in all bars, cafeterias and restaurants. Cafe solo is espresso minus the milk, while cafe Americano is Spain’s approximation of American coffee. A cafe con leche and a croissant usually costs between 250 and 350 pesetas.

The typical Spanish bar is the rough equivalent of a greasy-spoon diner in the United States. In many of them it is customary to spit olive pits and throw used napkins on the floor, which doubles as an ashtray.

Those homesick for familiar food can dine at McDonald’s, Burger King, Kentucky Fried Chicken or Pizza Hut, all of which are located near main tourist areas such as Las Ramblas.

At the upper end of the scale, Barcelona has no shortage of haute cuisine . But be careful: A meal for two can easily top $100 at the nicest places.

LANGUAGE Although Catalonia is a part of Spain, the predominant language throughout the region is Catalan, a distinct Romance language that sounds something like a mix of Spanish, Portuguese and French. Everyone speaks Spanish, however, and most people are patient with tourists from abroad who make at least a token effort to communicate.

COMMUNICATIONS Spanish telecommunications are sometimes frustrating, and always expensive when calling overseas. Hotels invariably tack on a surcharge to already stratospheric rates. If at all possible, use an AT&T;, Sprint or MCI operator when calling the United States.

To reach an AT&T; operator from Spain, dial 900-99-00-11.

To reach a Sprint operator from Spain, dial 900-99-00-13.

To reach an MCI operator from Spain, dial 900-99-00-14.

It costs 80 pesetas to mail a letter or postcard to the United States. Stamps are sold at the central post office at Placa Antoni Lopez, at tobacconists and at some hotels.

English-language newspapers and magazines are available at many newsstands, but are fairly expensive by American standards. For example, the International Herald Tribune and the Wall Street Journal Europe each cost 190 pesetas. USA Today costs 175 pesetas. Newsweek costs 350 pesetas.

FOR MORE INFORMATION Stop by the Barcelona tourist office at 658 Gran Via de les Corts Catalanes, near the Passeig de Gracia; local phone 301-7443.

From the United States, contact the National Tourist Office of Spain, 8383 Wilshire Blvd., Suite 960, Beverly Hills 90211, (213) 658-7188.