Baltimore Terminal Subdivision

The Baltimore Terminal Subdivision is a railroad line owned and operated by CSX Transportation in the U.S. state of Maryland. The line runs from Baltimore to Halethorpe along the original Baltimore and Ohio Railroad (B&O) line, one of the oldest rail lines in the United States and the first passenger railroad line. At its east (north) end, it connects with the Philadelphia Subdivision; its west (south) end has a junction with the Capital Subdivision and the Old Main Line Subdivision.

The B&O began construction in 1828. The original terminal was located in Baltimore at Pratt and Poppleton Streets. This location, initially a temporary wooden shed, became known as the Mount Clare Station. The Mount Clare Shops, the first railroad manufacturing facility in the U.S., was also built in this area. The rail line exited the city in a southwesterly direction. The company encountered varied terrain that required several large cut and fill earthmoving operations. The B&O built the Carrollton Viaduct, the first stone masonry bridge built for a U.S. railroad, during this project. The company provided an inaugural ride on the line from Pratt Street to the viaduct on New Year’s Day 1830. The bridge, a National Historic Landmark, is still used by CSX today. Construction of the tracks continued southward to the Patapsco River near Halethorpe, and then turned west following the river. Today Halethorpe is the southern terminus of the Baltimore Terminal Subdivision.

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