RF&P Subdivision

The RF&P Subdivision is a railroad line owned and operated by CSX Transportation. It runs from Washington, D.C. to Richmond, Virginia, over lines previously owned by the Pennsylvania Railroad and the Richmond, Fredericksburg and Potomac Railroad. The line's name pays homage to that railroad, which was a predecessor to the CSX.

At the northern (eastern) end of the line, the RF&P Sub connects to the Capital Subdivision, which runs to Baltimore, Maryland. Just before the Anacostia Railroad Bridge on the Capital Sub is the Virginia Avenue Tunnel. South (west) of the tunnel is a branch to the Amtrak First Street Tunnel, which leads to Union Station and the Northeast Corridor. The Virginia Avenue Tunnel is used only for freight trains, while the First Street Tunnel is used only for passenger trains.

Continuing south, the RF&P Sub crosses the Potomac River over the Long Bridge into Virginia, and passes through Alexandria and Fredericksburg, ending in Richmond at the Richmond Terminal Subdivision.

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