Baltimore Belt Line powerhouse exterior
View, looking northeast from the 300 block of West Henrietta Street, of the Baltimore Belt Line's South Howard Street powerhouse located in Baltimore, Maryland. People stand on the nearby train tracks. The building contained 500-Kw electrical generators that produced the power for electric locomotives to pull Baltimore & Ohio Railroad trains through the 1.4-mile long Howard Street Tunnel, as ventilation issues forbade the use of steam engines. The Baltimore Belt Line was constructed by the B&O in the early 1890s in order to connect its newly constructed line to Philadelphia and New York City with the rest of the railroad at Baltimore and included the Howard Street Tunnel, the Mount Royal Station, and the first mainline railroad electrification in the United States.