Designed by the architect Waddy Butler Wood, it was built between 1895 and 1897 by the Capital Traction Company as a union terminal for several Washington and Virginia streetcar lines.

Almost immediately after the building opened, Capital Traction converted its streetcar lines to electrical power and modified the Car Barn to suit.

Changing ownership over time, it maintained its original function of housing streetcars until 1950, when it was redeveloped as office space.

Among its occupants was the International Police Academy, an arm of the Central Intelligence Agency, which operated out of the Car Barn in the 1960s and 1970s.

[5][6] The legislation required that the railroad erect at the site a union passenger station in order to accommodate the street railway traffic expected to converge at or near the bridge.

[5] Construction on the building then known as Union Station began in early 1895 under the architectural direction of Waddy Butler Wood.

[10] The steps are so named as they provided the location for the scene in the 1973 horror film The Exorcist where the priest is thrown down the stairs to his death.

[12] After the Car Barn's construction, the large edifice obstructed the view of the Potomac River and Virginia from homes on Prospect Street, including the well-known cottage of E. D. E. N.

[13] The three-story, 180-by-242-foot (55 by 74 m) building was opened on May 27, 1897, containing offices for the several tenant trolley companies and waiting rooms that were decorated with red oak wainscot panelling, ornate iron stair railings, and stuccoed ceilings.

The pediment, which contains the words "Capital Traction Company", displays three decorative flywheels of the type that pull cables.

[16] Capital Traction expected trolleys to cross the Potomac River from Rosslyn on the nearby Aqueduct Bridge.

[15][17] Other trolleys were later expected to enter the building after traveling along the projected route of the Great Falls and Old Dominion Railroad.

[7] Almost immediately after the building opened, Capital Traction converted it to enable the company to operate the new electric streetcars.

The entrances to the building were extended to accommodate the larger cars, and a new elevator was installed to lift streetcars to the roof.

[25] In 1992, the owner of the DC Transit System, O. Roy Chalk, was subject to foreclosure, and the building came under the ownership of the Lutheran Brotherhood.

[28] Remnants of streetcar tracks and their central electrical conduit remain visible outside of the garage's east door on M Street.

Historic Preservation Office described the Car Barn as "the most significant extant example of a terminal or depot" in Washington, D.C.[35] The National Park Service added the building to the National Register of Historic Places as part of a multiple property submission named "Streetcar and Bus Resources of Washington, DC" on August 9, 2019.