Drinking outside in warm weather is hard to beat. Even in the wintertime, a hotel rooftop bar -- at least one that has either indoor space or a fleet of heat lamps (or both) -- is a great spot to unwind, so it's no wonder hotel rooftop bars across the country are highly sought after. Taking into account the scene, vibe, cocktails, and more, we've come up with a list of the 19 best hotel rooftop bars in the United States.