West Fairmount Park's "Playhouse in the Park" opened on July 30, 1952, as the nation's first municipally-owned and managed theater.

Famed Philadelphian John B. Kelly had given the impetus for its creation on the historic Belmont Mansion estate while he was President of the Fairmount Park Commission. The theater was initially a large tent offering seating capacity of 1,057.

It presented all manner of summer stock theater, with Broadway stars and playwrights contributing to its popularity. Margaret Truman (President Truman's daughter) and local star Grace Kelly (John Kelly's daughter) were among the luminaries who performed there.

A permanent wooden structure, a theater-in-the round with 1500 seats, replaced the tent in 1956. This was the first "theatre in the round" within a municipal park in the United States.

Philadelphia City Council eventually changed the theater's name to Kelly Playhouse to honor its founder. Unfortunately, the John B. Kelly Playhouse in the Park fell into disuse and
became vacant in 1979 after its last full season. The building was
demolished in 1997. The site is now a picnic grove.