Mount Airy is a neighborhood of Northwest Philadelphia in the U.S. state of Pennsylvania.

Northwest Philadelphia is a section of the city of Philadelphia. The official boundary is Stenton Avenue to the north, the Schuylkill River to the southwest, Northwestern Avenue to the northwest, Roosevelt Boulevard to the south, and Wister Street and Stenton Avenue to the east. Conventionally, the area east of Wissahickon Creek, which comprises Germantown, Mount Airy, Chestnut Hill, and Cedarbrook, is termed the 'Upper Northwest', and the area west of the creek, which comprises Roxborough, Wissahickon, East Falls, and Manayunk, is termed the 'Lower Northwest'. The area of Philadelphia west of the Schuylkill River is known as West Philadelphia. The Philadelphia Police Department patrols two districts located within Northwest Philadelphia. The two patrol districts serving Northwest Philadelphia are the 5th and 14th districts.