(FORTUNE Magazine) – Just a few years ago, wine bars were popping up across the U.S. from Chicago to Chattanooga. America was believed to be full of wine enthusiasts who would flock to places that provided a large variety of wines for sampling by the glass. But the nascent enophiles were fewer than imagined, and with low profit margins and heavy up-front costs (about $8,000 for a basic inventory and the special equipment needed to serve it), many bars soon closed. ( The good news is that survivors of the shakeout, along with some newcomers, are generally doing fine. For the traveler with even a passing interest in wine, the best wine bars afford a pleasant and entertaining alternative to a quick drink and heavy dinner. Good wines are easier to find than good advice. The mainstay of most wine bars is a machine called the Cruvinet, which draws wine out of bottles and replaces it with inert nitrogen, protecting it from spoiling for up to 30 days. Equipped with a Cruvinet or similar system, a bar can keep a dozen or more slow-moving wines in stock. But no machine can keep the staff fresh and up to date. I asked a bartender at a place in Boston (it will not be found among those reviewed) to describe a 1983 Chateau Montelena Cabernet Sauvignon from the Napa Valley. She replied, after a blank stare, ''It's a really heavy- duty red wine.'' Pressed for further specifics, she shrugged and returned to a telephone conversation with her boyfriend.

The bars below all carry at least a dozen decent wines. Usually the staff will also give you useful information -- but not always, so the more knowledge you bring the better. All serve food, take major credit cards, and unless otherwise noted are open seven days a week. Call for closing times: wine bars tend to shut down earlier (or thin out faster) than hard-liquor watering holes. California, America's wine heartland, paradoxically boasts few wine bars, possibly because Californians do a lot of sipping at home. But San Francisco's 12-year-old London Wine Bar, which claims to be the oldest in the country, is a model of its kind. With 600 wines, mainly from nearby Napa and Sonoma counties, it offers a constantly changing roster of about a dozen wines by the glass and eight to ten additional chalkboard listings that sometimes change hourly. Most range from $3 to $5 a glass; among the higher-priced entries are such boutique rarities as a 1984 Thomas Fogarty Chardonnay from the Portola Valley at $5.25. The edibles include an extensive selection of pates, cheeses, sandwiches, and other light fare. Some drawbacks: patrons, mainly from the financial district, tend to go home early, and the bar isn't open on weekends (415 Sansome; telephone: 415-788-4811). Exceptional wine bars flourish in Chicago. The most unusual and exciting is Pops For Champagne. Opened four years ago after owner Tom Verhey fell in love with a champagne bar in Vienna, Pops offers up to 20 champagnes by the glass, starting at $4, and 70 by the bottle. A rewarding splurge: the creamy 1979 Veuve Clicquot La Grande Dame for $15 a glass. A small menu of appetizers ranges from soup and quiche to caviar (2934 North Sheffield; 312-472-1000). The Chardonnay Wine Bar and Restaurant has a superb selection of 30 to 35 wines by the glass. Its list changes every two weeks, and each selection bears a chatty, informed critique. The Chardonnay serves full meals, including such dishes as Dover sole in a sauce made with pistachios and Johannisberg Riesling (2635 North Halsted; 477-5130; closed Mondays). Down the street at Cafe Royal, the lengthy wine list is a connoisseur's delight. Among the standouts: the little-known 1982 Mountain House Chardonnay from the Sonoma Valley, imbued with exhilarating sweetness by the botrytis mold, which produces prized dessert wines. The food is English: shepherd's pie, jugged hare, and the like (1633 North Halsted; 266-3394). Dallas has several wine bars, but it's no Chicago. La Cave is an attractive cafe and retail wine store, but when I asked a waiter the vintage of an Auxey-Duresses on the list, he said: ''Why don't you buy the bottle and find out?'' (2019 North Lamar; telephone: 214-871-2072). Though Zanzibar has a nice selection of two dozen wines and champagnes, the pulsing pop music and funky atmosphere may not be for everyone (2912 Greenville; 828-2250). The Wine Press is more sedate and the wine list is longer but the entries are pretty familiar (4217 Oak Lawn; 522-8720). In Atlanta, an agreeable seafood restaurant called the Fish Market offers 16 wines by the glass and plans to add ten or so more when it moves to larger quarters later this year. The selection is varied, but the bartender on a recent visit was not much help. Asked to describe an Australian Chardonnay, he seemed to pick the word ''oaky'' at random. It wasn't (3393 Peachtree Road in Lenox Square shopping center; 404-262-3165; closed Sundays). The Back Bay Bistro in Boston has an excellent selection of 25 wines by the glass, priced at $2.25 to $4.75. Descriptions are generally helpful, though sometimes overwrought: 1979 Chateau Gros Caillou, a robust St. Emilion, is described as ''firm, yet subtle and inviting'' (565 Boylston Street; 617-536-4477). Near Boston Harbor is Michael's Waterfront, a cheery bar with a healthy dose of singles action along its long mahogany bar. It is also a fine place to get a wine education, offering 19 wines in two-ounce tastings for as little as $1.25 each (85 Atlantic Avenue; 367-6425). New York has the biggest and best crop of wine bars in the country, and the best of these is the Soho Kitchen & Bar. This soaring industrial space, with 120-foot circular bar and late-night crowd that ranges from punks to investment bankers, boasts 96 wines and 14 champagnes. Soho Kitchen also provides 15 so-called flight tastings, series of wines chosen to contrast a single vineyard over several years or several comparable wines of the same year. Starting at $6.50, this fancy of flights allows you, for example, to have 1.5 ounces each of four dazzling dessert wines, including Chateau d'Yquem, for $21.50. The light menu includes pastas, seafoods, and excellent pizzas (103 Greene Street; 212-925-1866). Also in Soho is the engaging and informal Wine Bar, which serves 51 wines by the glass. The well-chosen list includes Italian, German, Spanish, and some Australian wines (422 West Broadway; 431-4790). In midtown the handsome, wood-paneled Lavin's offers 14 wines by the glass from a cellar of 400 wines. The tastings list changes twice a week and the bottle list twice a month. Seafood and desserts are especially good (23 West 39th Street; 921-1288; closed weekends). The Wine Bistro on the seventh floor of the Novotel Hotel has 21 well-selected wines and champagnes and its soaring glass-enclosed bar overlooking Times Square is a favorite business haunt (226 West 52nd Street; 315-0100). Tastings has as many as 30 wines by the glass, and is a popular business-lunch spot as well, serving such ''American continental'' food as chicken with riesling-mustard sauce (144 West 55th Street; 757-1160). Tastings on 2, a sister establishment on Second Avenue, offers up to 60 wines ( 953 Second Avenue; 644-6740). Manhattan's most exuberant wine bar is Grapes, on the Upper West Side. The decor is avant-garde, the rock music loud, and the patrons mostly young and casually dressed. But Grapes takes the grape seriously: roughly two dozen entries range from a 1980 Mouton Rothschild for $14 a glass to 1983 Quady Orange Muscat Essencia, an excellent dessert wine from Madera, California, for $2 (522 Columbus Avenue; 362-3004). At Grapes, as at other serious wine bars, a little curiosity can uncork a lot of enological pleasure.