The majority of those who pass through Grand Central Terminal don’t even realize they’re steps from this historic hideaway. In the ‘20s, it served as the office of railroad magnate John W. Campbell. The apartment — a popular bar for commuters, but a destination in its own right — channels poshness with its dark-wood-paneled walls, vaulted ceilings, and gigantic stone fireplace, with a balcony overlooking the main room. When it reopened in 2017 the Gerber Group added two more spaces: the Campbell Palm Court, which has the feel of a lobby in a turn-of-the-century colonial hotel, with views of the main terminal, and the Campbell Terrace, very casual outdoor seating in what used to be a taxi rank that wouldn’t seem out of place catering to the lunch crowd on Wall Street. Each of the three bars boasts entirely different vibes but shares one drink list. And it’s best to stick to the classics here. The martini is excellent but — even though a whole section of the menu is dedicated to them — you’re better off giving the old-fashioneds a miss: They are watered down and far too sweet.