It’s known as Bill’s, Bill’s Gay Nineties, and Bill’s 1890’s Restaurant & Café—and it is New York’s finest example of a 1920-1930 speakeasy. This time-warp restaurant is a piece of NY’s past. Those who walk down a few steps into the brownstone at 57 East 54th Street and push open the saloon swinging doors enter a world of dark wood, checkered table cloths, antique wrought iron chandeliers and bar lights, stained glass, creaking bare wood floor boards, mirrors and old photographs of boxers, baseball players and babes from another era.

Above the pub-y bar room, with its smattering of tables overlooking 54th St., is a large dining room with wood beams and a cathedral ceiling from the Vanderbilt mansion and fittings from the Waldorf, a piano, fireplace and a Lindy’s-like picture gallery of yesteryear’s leading ladies of showbiz.

The third floor private room sports a magnificent mahogany bar that came (depending on who tells the story) from either the Rockefeller mansion or Delmonico’s Restaurant. The eating place in this 140-year old building is run by Barbara Bart Olmsted whose father, O.B. Bart, loved Bill’s. In 1965, when it looked as though it might close, he purchased it and, in 1979, Ms. Olmsted took over.

All this history might make Bill’s seem like a museum. It isn’t. It’s a vibrant, hopping spot, with piano music (Mon.-Sat.) starting at 8 p.m., featuring some of NY’s top performers. Unlike most Midtown restaurants, weekends —especially Saturday nights—are slower.

The menu is straight forward, familiar, uncomplicated; shrimp cocktail, caesar salad, crab cakes, breast of chicken, steaks, New York cheese cake, and key lime pie. It’s also heavily tilted toward seafood. Indeed, the two most memorable dishes sampled at a recent dinner both came from the briny side of the menu. A New England clam chowder with chives floating on its surface, andserved in an oversize bowl was not the often-encountered thickened, gloppy brew. Rather it was delicate, sprinkled with potatoes and heavy on clams and flavor. Also in this class was a Saturday night special of sushi—rare, fresh sesame crusted Yellow Fin tuna with an interesting soy ginger glaze. Other noteworthy selections were a mountain of crispy calamari rings with a slightly spicy dipping sauce and mild, tasty, thin sliced Irish smoked salmon. The filet of salmon passed muster and crab cakes were tasty.

Desserts are house-made and good. The tangy key lime pie served with whipped cream is the star here. The warm apple and pear strudel with a scoop of vanilla ice cream and the intense chocolate mousse pie are also recommended as is the experience offered by Bill’s Gay Nineties.

57 E. 54th St. btw. Park & Madison Aves., 212-355-0243.