File:DC streetcar diagram.JPG
In 1911, McLean and Elkins formed a new corporation, the Washington and Old Dominion Railway.[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], p. 45.] In that year, they concluded negotiations with the Southern Railway to lease the Southern's Bluemont Branch and to take over all service on the branch on July 1, 1912.[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], p. 46.] The lease excluded the portion of the Southern's route that connected Potomac Yard with the former AL&H terminal in old town Alexandria.
In 1912, the GF&OD became the "Great Falls Division" of the W&OD Railway, while the Southern's Bluemont Branch became a part of the W&OD Railway's "Bluemont Division".[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], pp. 46, 49.] The W&OD electrified all of its operations over the next four years, becoming an interurban electric trolley system that carried passengers, mail, milk and freight.[Williams, pp. 45, 72.]
From that time onward, W&OD trains crossed over Potomac Yard, which opened in 1906, on a 1300-foot long trestle constructed around the same time for the Southern Railway.[Multiple sources:]
- [http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], pp. 32, 46–47.
- {{cite web|url=https://i.pinimg.com/originals/a8/1e/e0/a81ee0de0b84806a8788f908f31aaac1.jpg|title=W&OD bridge over Potomac Yard north of the Yard's St. Asaph station|format=photograph|via=Pinterest|access-date=October 22, 2018|archive-url=https://web.archive.org/web/20181022193023/https://i.pinimg.com/originals/a8/1e/e0/a81ee0de0b84806a8788f908f31aaac1.jpg|archive-date=October 22, 2018|url-status=live}} In contrast to the Southern Railway's earlier Bluemont Branch service, the W&OD Railway's Bluemont Division did not serve Washington Union Station.
[Williams, pp. 43–44.]
In the first few months, they invested in several upgrades to the system. To join its two lines, the W&OD Railway constructed a double-tracked Bluemont Division connecting line that traveled between two new junctions in Arlington: Bluemont Junction on the Alexandria-Bluemont line and Thrifton Junction on the Georgetown-Great Falls line.[Williams, p. 72.] They also constructed a turning wye at Bluemont Junction which ended between 7th and 8th street N. The connecting line passed through Lacey (near the west end of Ballston), crossing on a through girder bridge over a competing interurban electric trolley line, the Fairfax line of the Washington-Virginia Railway (see Northern Virginia trolleys).[Williams, pp. 107, 144, 156.][{{cite web |url=http://www.hmdb.org/Marker.asp?Marker=64845 |title="Lacey Car Barn" marker |publisher=HMdb.org: The Historical Marker Database|access-date=October 14, 2017|quote=In 1896, the Washington, Arlington & Falls Church Railway began running electric trolleys from Rosslyn to Falls Church on the present routes of Fairfax Drive and I-66. By 1907, the line linked downtown Washington to Ballston, Vienna, and the Town of Fairfax. In 1910, the railway built at this location a car barn, rail yard, workshop, electrical substation, and general office. In 1912, the rival Washington & Old Dominion Railway began crossing the tracks on a bridge 200 yards west of here, traveling the present route of I-66 from Rosslyn. The line to Fairfax closed in 1939, but Metrorail's Orange Line follows its route through Arlington.|archive-url=https://web.archive.org/web/20171014160828/https://www.hmdb.org/Marker.asp?Marker=64845 |archive-date=October 14, 2017|url-status=live}}] By October 1912 they had electrified the Bluemont Division from Bluemont Junction to Leesburg and by December all the way to Bluemont.
Most of the Bluemont Division's passenger cars or trains ran on the W&OD Railway's Great Falls Division's line from Georgetown over the Aqueduct Bridge through Rosslyn to Thrifton Junction. From Thrifton Junction, the trains ran on the Bluemont Division's connecting line to Bluemont Junction, where they met other Bluemont Division passenger cars or trains that ran from Alexandria, following Four Mile Run in Arlington. Some of the Bluemont Division cars or trains then continued their trips through Falls Church, Vienna, Herndon, Sterling, Ashburn, Leesburg, Clarke's Gap and Purcellville to terminate in Bluemont, Virginia, at the base of the Blue Ridge Mountains, following a route that was similar to that of Virginia State Route 7.[Multiple sources:]
- Williams, p. 43.
- Washington and Old Dominion Railway timetables:
Bluemont Division: Williams, pp. 40, 68.
Great Falls Division: Williams, p. 67.
The railway's electrification system distributed 650 volts direct current (DC) to its Bluemont Division cars and trains through overhead catenary lines, even though by 1912 this system was becoming obsolete by 1200 V systems.[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], pp. 48–49.] Single overhead lines carried the Great Falls Division's electricity over its tracks.[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], pp. 39, 48–49.] Stationary and movable electrical substations containing Westinghouse alternating current (AC) to DC converters were located at Round Hill, Leesburg, Herndon, and Bluemont Junction. .[Williams, pp. 70–71.]
The W&OD's main passenger line ran from Georgetown and Rosslyn through Thrifton Junction, Bluemont Junction and westward to Bluemont.[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], p. 47.] However, after crossing the Potomac River from Georgetown, many W&OD passengers transferred in Rosslyn to the trolleys of the competing Washington-Virginia Railway.[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], p. 38.] Most of the W&OD's freight trains ran between Potomac Yard, Bluemont Junction and either Rosslyn or various locations along the Bluemont Division.
In 1917, John McLean died from cancer and the railroad ownership passed to his heirs and those of Elkins. The heirs had little interest in running the railroad and in 1918 and 1922 the Virginia Corporation Commission ordered the railroad to make improvements, which the absentee owners never did.
In 1923, the W&OD Railway ceased operating from Georgetown when the federal government replaced the aging Aqueduct Bridge with the new Francis Scott Key Bridge.[Multiple sources:]
- Williams, p. 74.
- [http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], pp. 68–69. At the same time, the railroad constructed a new passenger station in Rosslyn which became its "Washington" terminal.
The W&OD Railway lost money every year after 1912 and fell upon particularly hard times during the Great Depression.[Multiple sources:]
- Williams, pp. 74, 93.
- [http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], pp. 73–79. In 1932, the railway went into bankruptcy and was again placed in receivership.
[Multiple sources:]
- Williams, p. 93.
- [http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], p. 73. The receivers chose new management that cut employees, service and rolling stock in an effort to reduce costs. To further cut costs, the railway abandoned operations on the Great Falls Division between Thrifton Junction and Great Falls in stages with the process completed in June 1934, with the last train run on June 8. Several of the cars that ran on the Great Falls line were dismantled later that year and the tracks were pulled up in mid-1935. The abandoned railway route then became Old Dominion Drive (Virginia State Route 309).
[[http://www.scc.virginia.gov/docketsearch/DOCS/198p01!.PDF Harwood], pp. 77–78.][King, 1934 (map)] In 1979, the Great Falls Divisions old rail trestle over Difficult Run, the last physical piece of rail infrastructure still in use from that line, was demolished after years of carrying automobile traffic on Old Dominion Drive.[{{cite news |last1=Hanson |first1=Christoper |title=A Rusted Old Trestle Falls, A Relic of the Car Era |work=The Evening Star |date=April 9, 1979}}] In addition, the receivers also ended passenger service between Bluemont Junction and Alexandria in 1934. With the reduced service they were able to cut their rolling stock by more than half that year.