Metropolitan Subdivision

Construction began in 1866 along a slightly different route, connecting with the main line at Point of Rocks, Maryland.

Several distinctive passenger stations, designed by architect Ephraim Francis Baldwin, were constructed along the line.

Original stations still stand in the Maryland communities of Rockville (moved away from the tracks in 1981), Kensington, Gaithersburg, Dickerson, and Point of Rocks.

On February 16, 1996, the collision of two trains in Silver Spring killed three crew members and eight passengers and injured a total of 26 people.

The first, completed in 1892, ran from the junction along the northern bank of Coquelin Run to a new extension of Connecticut Avenue in the nascent development of Chevy Chase.

[6]: 27–29  Engineering features of the branch included the Rock Creek Trestle in Chevy Chase, the Dalecarlia Tunnel, and a through-truss bridge over the Chesapeake and Ohio Canal.

CSX ran its last train on the Georgetown Branch in 1985 after a bridge in Montgomery County was found to have structural problems, and launched the abandonment process the year after 75 feet of track was damaged in the 1985 Election Day floods.

In 2017, construction began on the Purple Line, which will use the Bethesda-to-Silver Spring portion of the spur as part of a route that continues on to New Carrollton, Maryland.

Westbound CSX autorack train on the Metropolitan Subdivision in Point of Rocks
The stone arch railroad bridge built over the newly-diverted Rock Creek in 1893 now passes over Beach Drive and the bike path
Rockville station in 1978, before it was moved away from the tracks
Georgetown Branch in Bethesda, Maryland, near where it crossed Bethesda Avenue
Freight train at Derwood interlocking heading east towards Washington, D.C.
The Dickerson spur splits off to the left, while the Monocacy River is just beyond the curve.