The original museum operating line consisted of a one-half-mile section of the abandoned Pittsburgh Railways Co. Washington interurban line which until 1953 connected to Pittsburgh via the route that still serves sections of Bethel Park. The museum line was extended north along the track bed of the abandoned Pennsylvania Railroad branch to the Arden Mines. Between 1979 and 1995, museum volunteers constructed new (5'2-1/2 gauge) track along this right of way to a location near the former coal mining town. This added to the track and allowed stations to be opened at the County Fairground and Arden Mines, where a loop track was constructed, simplifying the operation of cars. In 2004, the original museum track was extended along the original interurban route to a point near North Main Street and Country Club Road. At this site another loop (McClane School Loop) was constructed, making possible the continuous operation of single-ended trolleys. Tracks connecting to the Trolley Display Building, attached to this section of the line, were opened in 2008.