A truly historic cocktail bar in a glamorous old hotel, once tended by such luminaries as Ada Coleman and Harry Craddock. As one might expect, the drinks are very expensive--expect to pay up to twice as much as anywhere else, and much, much more for the vintage cocktails--but well-executed. The service was very good and the art deco atmosphere wonderful, though it was marred a bit by the loud live piano jazz. We walked in with no reservations and had to wait a few minutes, but this gave us the chance to check out the hotel's American Bar museum (lots of Sinatra!). Make sure to walk about the hotel a bit too; it really is a gorgeous old place. Cocktails tried and recommended: Classic Dry Martini, Green Park.