RoofTop Pool (pictured): This aquatic hot spot, situated a dozen stories above the Back Bay and open to non-hotel guests for a fee Monday–Friday, boasts private cabanas, a bar, food service, Wednesday morning yoga classes and live music Tuesday and Thursday evenings.

Rooftop@Revere: Featuring a heated, indoor pool and cabana rentals, this seventh-story terrace overlooking the Theatre District—complete with a full bar and serving seasonal New England fare—offers guest passes to the 21-plus crowd.

Boston Common Frog Pond: Families flock to this landmark year-round, as the winter skating rink is converted into a summer wading pool and spray fountain, complemented by a nearby carousel.

Rose Kennedy Greenway: This centrally located park hosts an array of spray fountains and water features, including the popular Rings Fountain that jets water several stories in the air, the cooling mists and soothing sounds of Ross Miller’s interactive Harbor Fog Sculpture and Chinatown’s bamboo-accented wading stream.

Christian Science Plaza: The Children’s Fountain at this Fenway institution offers cooling fun for your little ones throughout the hotter months.