BUSINESS HOURS

In most cases (liquor stores being a notable exception), shops can set their own hours. Most open between 8 AM and 10 AM and shut between 6 PM and 7 PM; many open on weekends, too. Banks operate weekdays from 9 AM until 2 PM or 3 PM, and some are also open on Saturday mornings. Post offices are open weekdays 8 AM-5 PM and Saturday mornings. Holidays January 1 (New Year's Day); third Monday in January (Martin Luther King Jr. Day); third Monday in February (President's Day); last Monday in May (Memorial Day); July 4 (Independence Day); first Monday in September (Labor Day); second Monday in October (Columbus Day); November 11 (Veterans Day); fourth Thursday in November (Thanksgiving Day); December 25 (Christmas).

CUSTOMS & DUTIES

Foreign visitors age 21 or older may import the following into the United States: 200 cigarettes or 50 cigars or 2 kilograms of tobacco; 1 liter of alcohol; gifts to the value of $100. Restricted items include meat products, seeds, plants, Cuban cigars, and fruits. Never carry illegal drugs.

EMERGENCIES

For police, fire, or ambulance, telephone 911. Hospital Emergency Rooms Two hospitals with 24-hour emergency rooms are San Francisco General Hospital (1001 Potrero Ave., tel. 415/206-8000) and the Medical Center at the University of California, San Francisco (500 Parnassus Ave. at 3rd Ave., near Golden Gate Park, tel. 415/476-1000). Doctors and Dentists Davies Medical Center Physician Referral Service (tel. 415/565-6333). 1-800-DENTIST (tel. 800/336-8478) St. Luke's Hospital Physician Referral Service (tel. 415/821-3627) San Francisco Dental Society Referral Service (tel. 415/421-1435). 24-HOUR PHARMACIES Several Walgreens Drug Stores have 24-hour pharmacies (498 Castro, at 18th St., tel. 415/861-3136; 25 Point Lobos, near 42nd Ave. and Geary St., 415/386-0736; and 3201 Divisadero St., at Lombard St., tel. 415/931-6417). The downtown Walgreens pharmacy (135 Powell St., near Market St., tel. 415/391-7222) is open weekdays 8-8, Saturday 9-5, and Sunday 10-6.

MAIL

Sending Mail Home First-class letters (under one ounce) sent within the United States cost 33 cents; postcards are 20 cents. A one-ounce letter to Canada takes a 48-cent stamp and a postcard 45 cents; for Mexico, you'll need a 40-cent stamp for a half-ounce letter and 40 cents for a postcard. Airmail letters (under a half ounce) to other overseas destinations cost 60 cents, and postcards are 55 cents. For 60 cents, you can also buy an aerogram -- a pre-stamped sheet of lightweight blue paper that folds into its own envelope. You can purchase stamps from post offices, as well as from small vending machines in gift stores, drug stores, airports, and bus and train stations. To mail oversized letters and packages, head for the post office or to one of the many private mail-handling stores such as Mail Boxes Etc., although these tend to charge a hefty commission.   EXPRESS MAIL The U.S. Post Office offers overnight express mail service to certain domestic and international locations. For more extensive service, contact a private shipping company such as Federal Express (tel. 800/463-3339), DHL Worldwide Express (tel. 800/225-5345), Airborne Express (tel. 800/247-2676), or United Parcel Service (UPS, tel. 800/742-5877).   Receiving Mail To receive mail while in San Francisco, have it sent to your name, c/o General Delivery (101 Hyde St., San Francisco, CA 94142) . Your mail will be held for up to 30 days. You must pick it up in person and bring identification with you. Otherwise, you can have mail sent to the nearest American Express office (455 Market St., San Francisco, CA 94105, tel. 415/512-8250), which also offers a general-delivery service. There's no charge for cardholders, holders of American Express Traveler's checks, or anyone who booked a vacation with American Express.

MONEY

The basic unit of U.S. currency is the dollar, subdivided into 100 cents. The commonly used paper notes are the $1, $5, $10, $20, $50, and $100 dollar bills. The green and white bills are all uniform in size and feature the picture of a prominent figure or monument in American history. There are six U.S. coins: the copper penny or cent, the silver nickel (5 cents), the dime (10 cents), the quarter (25 cents), the half dollar, and the rarely used one-dollar coin, also known as the Susan B. Anthony dollar. Taxes California levies an 8.5% sales tax that applies to most products and all restaurant meals, and a 12% hotel tax (know bizarrely as transient occupancy tax) that adds significantly to the cost of a long stay in San Francisco.

PACKING

When packing for a vacation in the San Francisco Bay Area, prepare for temperature variations. An hour's drive can take you up or down many degrees, and the variation from daytime to nighttime in a single location is often marked. Take along sweaters, jackets, and clothes for layering as your best insurance for coping with variations in temperature. Include shorts or cool cottons for summer, and always tuck in a bathing suit, since most lodgings include a pool. Bear in mind, though, that the city can be chilly at any time of the year, especially in summer, when the fog is apt to descend and stay. Although casual dressing is a hallmark of the California lifestyle, men will need a jacket and tie for many good restaurants in the evening, and women will be more comfortable in something dressier than regulation sightseeing garb. Electricity Overseas visitors will need to bring adapters to convert their personal appliances to the U.S. standard: AC, 110 volts/60 cycles, with a plug of two flat pins set parallel to one another.

PASSPORTS & VISAS

Canadians No passport is necessary to enter the United States. U.K. Citizens British citizens need a valid passport to enter the United States. If you are staying for fewer than 90 days and traveling on a vacation, with a return or onward ticket, you probably will not need a visa. However, you will need to fill out the Visa Waiver Form, 1-94W, supplied by the airline.

SIGHTSEEING TOURS

Orientation Golden Gate Tours (tel. 415/788-5775) uses both vans and buses for its 3 1/2-hour city tour ($30), offered mornings and afternoons. You can combine the tour with a bay cruise ($38). Customers are picked up at hotels and motels. Senior-citizen and group rates are available. Tours daily; reserve a day ahead. Gray Line (tel. 415/558-9400) offers a variety of tours of the city, the Bay Area, and northern California. The city tour ($16-$32), on buses or double-decker buses, lasts 3 1/2 hours and departs from the Transbay Terminal at 1st and Mission streets five to six times daily. Gray Line also picks up at centrally located hotels. Make reservations the day before. The Great Pacific Tour (tel. 415/626-4499) uses 13-passenger vans for its daily 3 1/2-hour city tour ($32). Bilingual guides may be requested, and they pick up at major San Francisco hotels. Tours are available to Monterey, the Wine Country, and Muir Woods. Tours daily; reserve a day ahead or, possibly, the same day. Tower Tours (tel. 415/434-8687) uses 20-passenger vans for city tours and 25-passenger buses for trips outside San Francisco to Muir Woods and Sausalito, the Wine Country, Monterey and Carmel, and Yosemite. The city tour runs 3 1/2 hours ($25). The Wine Country tour includes the historic Sonoma town square. Tours daily; make reservations the day before. Walking Tours Castro District: Trevor Hailey (tel. 415/550-8110) leads a 3 1/2-hour tour focusing on the history and development of the city's gay and lesbian community, including restored Victorian homes, shops and cafés, and the NAMES Project, home of the AIDS memorial quilt. Tours depart at 10 AM Tuesday-Saturday from Castro and Market streets. Cost: $30, including brunch. Chinatown with the "Wok Wiz": Cookbook author Shirley Fong-Torres (tel. 415/981-8989) leads a 3 1/2-hour tour of Chinese markets, other businesses, and a fortune-cookie factory. Cost: $35 including lunch, $25 without lunch. Shorter tours start at $15. Chinese Cultural Heritage Foundation (tel. 415/986-1822) offers two walking tours of Chinatown. The Heritage Walk leaves Saturday at 2 PM and lasts about two hours; cost is $12. The Culinary Walk, a three-hour stroll through the markets and food shops, plus a dim sum lunch, is held every Wednesday at 10:30 AM: $25 adults, $10 children under 12. City Guides (tel. 415/557-4266), a free service sponsored by Friends of the Library, offers the greatest variety of walks, seven days a week. They include Chinatown, North Beach, Coit Tower, Pacific Heights mansions, Japantown, the Haight-Ashbury, historic Market Street, the Palace Hotel, and downtown roof gardens and atriums. Schedules are available at the San Francisco Visitors Center at Powell and Market streets and at library branches.

TELEPHONES

The country code for the United States is 1. The 415 area code is used in San Francisco and Marin County. The area code south of San Francisco on the Peninsula is 650. San Jose and other South Bay cities use 408. Oakland and Berkeley use 510, and a new 925 area code covers the area east of the Oakland Hills, from Walnut Creek to Concord to Moraga. The area code in the Wine Country is 707. You do not need to dial the three-digit area code when making a call from within the same code. When calling a number in another area code, dial 1 followed by the area code and the telephone number. Telephone numbers beginning with 800 or 888 are toll-free numbers that can be dialed without charge from anywhere in the country. Numbers beginning with 900 are special toll numbers that usually offer some kind of service, such as horoscope readings, weather reports, sports scores, or sexually explicit conversations; they may charge several dollars per minute. Long Distance International calls can be dialed directly from most phones; dial 011 followed by the country code and then the local number. To have an operator assist you, dial 0. To avoid hotel surcharges, you can place a call directly through a long-distance company--AT&T, MCI or Sprint--if you've got an account with them. If you don't have an account, you can charge a call to a major credit card by calling AT&T directly at 800/225-5288. Operator Assistance For operator assistance, dial 0. To find out a telephone number, call directory assistance at 555-1212; if you're requesting a number from another area code, don't forget to dial 1 and the area code first. If you want to reverse the charges (known in the U.S. as a collect call), dial 0 and then the rest of the number, and an operator or automated voice will assist you. Pay Phones The most common pay phone in operation today is the coin-operated type. To use one, pick up the receiver, deposit your money (the minimum amount is posted on the machine), and then dial the number. An automated message will alert you to deposit more money, if needed. Telephone-card phones, so popular elsewhere in the world, are becoming increasingly common. Grocery stores, newsstands, and other establishments sell the disposable phone cards, available in varying amounts from $5 and up. To activate the card, dial the code number and follow the instructions printed on the card.

TIPPING

Tipping is common practice. In restaurants, tip waiters about 15% and as much as 20% in very expensive places. The same applies to bartenders, taxi drivers, and hairdressers. Unless otherwise posted, tip $1 per coat at a coat check; 50 cents per bag for bellhops; and $1 a day for maids in upscale hotels. On package tours, drivers and conductors usually get $2-$3 per day from each group member; check first to see if tips are included in the cost. For local sightseeing tours, tip the driver $1 if he or she has been helpful or informative.

VISITOR INFORMATION

Tourist Offices IN SAN FRANCISCO Contact the San Francisco Convention and Visitors Bureau (Box 429097, San Francisco, CA 94142-9097, tel. 415/974-6900). The Redwood Empire Association Visitor Information Center (The Cannery, 2801 Leavenworth St., 2nd floor, 94133, tel. 800/200-8334) covers San Francisco and surrounding areas, including the Wine Country, the redwood groves, and northwestern California. The California Office of Tourism (801 K St., Suite 1600, Sacramento 95814, tel. 916/322-2882 or 800/862-2543) can answer many questions about travel in the state. AT HOME In the United Kingdom, contact the United States Travel and Tourism Administration (Box 1EN, London W1A 1EN, tel. 020/7495-4466). For a free USA pack, write the USTTA at Box 170, Ashford, Kent TN24 0ZX; enclose stamps worth £1.50. Canadian travelers can contact Travel USA (tel. 905/890-5662 or 800/268-3482 in Ontario).   Better Business Bureau Contact San Francisco's Better Business Bureau (114 Sansome St., Suite 1103, 94104, tel. 415/243-9999). Chambers of Commerce There are chambers of commerce in dozens of San Francisco Bay Area towns, including Berkeley (1834 University Ave., Box 210, Berkeley, 94703, tel. 510/549-7040), and convention and visitors bureaus in Oakland (1000 Broadway, Suite 200, Oakland 94607, tel. 510/839-9000 or 800/262-5526), San Jose (333 W. San Carlos St., Suite 1000, San Jose 95110, tel. 408/295-9600 or 800/726-5673), and Santa Clara (2200 Laurelwood Rd., Santa Clara, 95054, tel. 408/970-9825). Travel Agencies The American Express Travel Service (455 Market St., San Francisco, CA 94105, tel. 415/512-8250) is open weekdays 8:30-5:30, Saturday 9-2.

WHEN TO GO

You can visit San Francisco comfortably any time of year; the climate here always feels Mediterranean and moderate--albeit with a foggy, sometimes chilly twist. The temperature rarely drops lower than 40°F, and anything warmer than 80°F is considered a heat wave. North, east, and south of the city, summers are warmer. Shirtsleeves and thin cottons are usually fine for the Wine Country. Be prepared for rain in winter, especially December and January. Winds off the ocean can add to the chill factor, so pack warm clothing. Climate What follows are the average daily maximum and minimum temperatures for San Francisco: May-October: 48-73°F (9-23°C); November-April: 41-64°F (5-18°C). Festivals & Seasonal Events WINTER December As the first American city to perform the full-length Nutcracker (tel. 415/703-9400), San Francisco remains one of the best places to see the well-known Christmas ballet. The annual Sing-It-Yourself Messiah (tel. 415/864-6000) takes place at Davies Symphony Hall on two nights during the first week of the month. The New Pickle Circus (tel. 415/544-9344), a particularly joyous group that started as a band of street performers during the early 1970s, performs annually during the holiday season at the Palace of Fine Arts Theater in the Marina District or at nearby Fort Mason. January The Shrine East-West All-Star Football Classic, America's oldest all-star sports event, takes place in the Stanford University Stadium (1651 19th Ave., 94122, tel. 415/661-0291) in Palo Alto, some 25 miles south of San Francisco. January-April Whale-watching can be enjoyed throughout the winter, when hundreds of gray whales migrate along the Pacific coast. Contact the California Office of Tourism (801 K St., Suite 1600, Sacramento 95814, tel. 800/862-2543). February The Chinese New Year celebration in San Francisco's Chinese community, North America's largest, lasts for two weeks, culminating with the justly famous Golden Dragon Parade and fireworks, "to scare away the evil spirits." For a complete schedule of events, send a stamped, self-addressed envelope to the Chinese Chamber of Commerce (730 Sacramento St., 94108, tel. 415/982-3071). SPRING March On the Sunday closest to March 17, San Francisco's St. Patrick's Day celebration includes snake races and a long parade through the downtown area. April The Cherry Blossom Festival, an elaborate presentation of Japanese culture and customs, winds up with a colorful parade through San Francisco's Japantown. Contact the Japan Center (1520 Webster St., 94115, tel. 415/922-6776). May-June Carnaval, held in the Mission District, includes a parade, a street festival, and a costume contest. May Thousands sign up to run the San Francisco Examiner Bay to Breakers Race (Examiner Bay to Breakers, Box 7260, 94120, tel. 415/777-7770), a 7 1/2-mile route from bay side to oceanside that's a hallowed San Francisco tradition. SUMMER June The North Beach Festival, every Father's Day weekend, transforms Washington Square Park and Grant Avenue into an Italian marketplace, with food, music, and entertainment. The Lesbian, Gay, Bisexual, and Transgendered Freedom Day Parade and Celebration (tel. 415/864-3733) winds its way from the Civic Center to the Embarcadero on the third or fourth Sunday. July The Fourth of July celebration, at Crissy Field in the Presidio, features family festivities beginning in mid-afternoon and a fireworks display at 9 PM. The Cable Car Bell-Ringing Championship (tel. 415/923-6162) is on the third Thursday of July at noon in Union Square. AUTUMN September Opera in the Park (tel. 415/864-3330) takes place in Golden Gate Park on the Sunday after Labor Day. The San Francisco Blues Festival (tel. 415/826-6837), on the Great Meadow at Fort Mason, is held on the third weekend of September. October Beginning the second weekend of the month, Fleet Week celebrates the Navy's first day with a Blue Angels air show over Pier 39 and the Bay. On the Sunday closest to Columbus Day, a weekend festival of Italian food and music kicks off the Columbus Day celebration (678 Green St., 94133, tel. 415/434-1492), which also includes a parade through North Beach.