What ultimately became the Sprain Brook Parkway began taking form in the 1920s, when the Westchester County Road Commission acquired the right-of-way for a planned extension of the Taconic State Parkway. The land, bought from 1925 to 1927 for $1.5 million ($ in modern dollars), was, however, not used as a parkway, and in 1938, was proposed to be used instead as an arterial state highway, rather than a parkway. The commission sent a request in April 1938 to the State Council of Parks to have the state take over the right-of-way after the state withdrew its support for the parkway extension. In April 1938, the county was approached by the Westchester County Park Commission to transfer the new project to the state for construction by the State Council of Parks. The project, which at the time would have cost $7 million ($ in modern dollars), was to connect to the Robert Moses-proposed highway between New York City and Albany.