18 Ninth Ave.
Elbow your way into the elevator and travel up to the hip and hellishly crowded Plunge, in the 14th-floor penthouse of the Hotel Gansevoort. You’ll exit directly into the bar area—open when the weather is warm and covered by a glass greenhouse-like structure when it’s rainy or chilly. To the left, there's an outdoor pool, but Plunge is a pretty misleading name because try as you may, you’re not allowed near it. The pool is for registered guests only: We snuck in, were greeted by a large slug clinging to the rim of the pool, then were told to "beat it" by the lifeguard. The inside lounge area is filled with low leather settees and mini skirt–wearing, Marc Jacobs–bag-toting scenesters. If it's hot and crowded, this room is unbearable. Try to get a seat in the narrow wraparound outdoor space which has scattered black, trendy chairs and benches and plastic stools. While sipping an overpriced cocktail (a basic rum and coke costs $15), soak up the fantastic view of the river and New Jersey, then look directly down on the SoHo House’s lovely pool, a celebrity favorite. Plunge is filled to capacity on weekends with trendy young things hoping to see and be seen. Our advice: Go on a Monday or Tuesday night for a quiet (albeit expensive) drink, and enjoy the view in peace.