daily into and around the city. The El once powered the economic engine of West Philadelphia. Retail districts lined every street where there was a station as well as along Market Street. Most recently many of these retail districts with the exception of 52nd Street have been converted to largely residential areas. One of the aggravating factors in this change has been the recent reconstruction of the EL which, due to detours of the "number streets" or numbered north–south thoroughfares and closure of large portions of Market Street, have led to many remaining businesses failing. Light rail Another major transit link in West Philadelphia are the five Subway Surface Lines, often called the Green Lines for their representation on SEPTA route maps. These include five of Philadelphia's remaining six streetcar lines. Combined, these trolley routes convey more than 150,000 passengers daily, and operate 24-hour schedules, even in blizzards. The Route 10 trolley runs along Lancaster Avenue from 63rd and Malvern Avenue through to 36th and Ludlow Streets where a portal allows access to the subway tunnel into Center City. The Route 34 trolley runs along Baltimore Avenue from Cobbs Creek at 61st Street to the transit tunnel at 40th Street in University City. The Route 13 trolley runs along Chester Avenue from the transit tunnel at 40th Street and Baltimore Avenue to 67th Street where it turns off Chester Avenue and continues along PA Route 13 into Yeadon, Delaware County on to its terminus at Green Lane. The Route 11 trolley runs along Woodland Avenue from the transit tunnel at 40th Street to the city line at Cobbs Creek and continues into Darby Borough. Finally, the Route 36 trolley is the longest trolley Green Line service. The 36 trolley leaves the 40th Street transit tunnel running along Woodland Avenue until 49th Street where it turns south to continue along Lindbergh Boulevard turning at Elmwood Avenue starting at 55th Street. Route 36 terminates in Southwest Philadelphia at Island Avenue west and 73rd Street, near the Philadelphia International Airport. Two other trolley lines originally ran through West Philly. The Route 38 trolley, running from Wynfield to Center City via Belmont Avenue, and the Route 31 trolley, running from Overbrook to Center City via Haverford Avenue, were replaced by diesel buses when the Philadelphia Transportation Company transferred control of the trolley service to National City Lines. Regional rail West Philadelphia is also served