The Arlington Historical Society tracks ‘This Day In History’ on its Facebook page. Here’s their listing for April 20th.
April 20 is the day in 1810 when Congress passed an act that created Columbia Pike. By this action, Congress chartered a turnpike company to build three separate roads through the newly formed District of Columbia — which until 1846 included what is now Arlington County — to outlying destinations.
One of the three roads was to be built through a portion of the District of Columbia, that had previously been part of Virginia, to connect access westward from the new Long Bridge (which predated the 14th Street Bridge) to the Little River Turnpike Road. (Another planned section of Columbia Pike would connect Washington and Baltimore on the Maryland side.) The new Virginia road was built on a pre-existing cow path known variously as either the Washington Graveled Turnpike, the Washington Road, the Columbian Road, and/or the Arlington Turnpike.
Benjamin Henry Latrobe, the Second Architect of the Capitol, was also the lead on the Commission to survey and build the road. Latrobe faced significant pressure from prominent individuals to alter the planned route. The road was built from 1812-1815 at a cost of approximately $40,000.