USA – Pittsburgh Railways M551 (seen July 2025)

Before the modern PATransit light rail, Pittsburgh Railways had over 600 miles of trolley lines at the end of World War 1, and had a large fleet of maintenance-of-way railcars that drew power from the same overhead trolley wires as the streetcars. Side dump car M551 (Differential Car Company, 1922) operated until 1984, even receiving new cabs at the PATransit workshop in 1977, and joined the Pennsylvania Trolley Museum the same year it was retired. It continues working for the museum and helped rebuild the roadbed washed out by Hurricane Ivan in 2004.