I drew a very, very large map of the trolley system before it was dismantled. This is based on a 1940 original made by the privately-owned Philadelphia Transportation Co. : r/philadelphia
SEPTA to replace Girard Ave. trolleys with bus service - WHYY
Open Thread: What would your ideal Philly subway system look like? - Curbed Philly
SEPTA's 101 and 102 Trolley Lines - Philadelphia PA
Subway–Surface Trolley Lines in Philadelphia 2017 - YouTube
SEPTA proposes name change for subway, trolley lines