Aire Ancient Baths
This subterranean spa in the heart of TriBeCa is known as one of the swankiest spas in the city. It's a unique atmosphere of relaxation where you take a journey through sensations across various baths. Book a private bath enhanced with milk, citrus juice, olive oil or red wine. Keep in mind that special treatments and access to the thermal pools will run you about $450-$500. No wonder celebrities love the place.
Aire Ancient Baths, 88 Franklin St.
[Photo via @aireancientbaths_us]