Logan Square is a neighborhood in Philadelphia, Pennsylvania, United States. Bounded by Market Street on the south, Spring Garden Street on the north, Broad Street on the east, and the Schuylkill River on the west, it occupies the northwestern quadrant of Center City. The square for which it is named is one of the five squares central to William Penn's design for Philadelphia. Originally called Northwest Square, it was renamed in honor of James Logan, an 18th-century mayor of Philadelphia.

Center City includes the central business district and central neighborhoods of Philadelphia, Pennsylvania, United States. It comprises the area that made up the City of Philadelphia prior to the Act of Consolidation, 1854, which extended the city borders to be coterminous with Philadelphia County.