B (SEPTA Metro)

The B, formerly known as the Broad Street Line (BSL), is a rapid transit line in the SEPTA Metro network in Philadelphia, Pennsylvania, United States. The line runs primarily north–south under Broad Street from the Fern Rock Transit Center in North Philadelphia through Center City Philadelphia to NRG Station at Pattison Avenue in South Philadelphia. The Ridge spur follows Ridge Avenue between Fairmount Avenue and Market Street.

The line, which is entirely underground except for the northern terminus at Fern Rock, has four tracks in a local/express configuration from Fern Rock to Walnut–Locust and two tracks in the southern portion. With about 115,000 boardings on an average weekday in 2019, it is the second-busiest route in the SEPTA system.

Route and services

The B runs in the Broad Street Subway, which runs north–south under Broad Street between NRG Station at Pattison Avenue in South Philadelphia and Olney Transit Center at Olney Avenue in Logan. North of Olney Avenue, the line curves east to Fern Rock Transit Center, the only surface-level station on the line. Between Lombard–South station and just west of Fern Rock, the subway is quadrupled-tracked with inner express tracks and outer local tracks. Express stations have two island platforms serving all four tracks, while local stations have two side platforms serving only the outer tracks. South of Walnut-Locust and at Fern Rock, the line has two tracks and single island platforms.