The oldest continually operating restaurant in New York City (since 1837), austere Delmonico's is steeped in cultural, political, and culinary history. Lobster Newburg and Baked Alaska were invented here—and are still served. Inside the stately mahogany-panel dining room, tuck into the classic Delmonico's steak, a 20-ounce boneless ribeye smothered with frizzled onions, and don't forget to order creamed spinach on the side. The cheesy spaetzle with pancetta is also sinfully sublime. The dining room gets busy early with an after-work Wall Street crowd, making reservations essential.