Under the New Deal of Franklin Delano Roosevelt, the federal government got involved in urban planning. One hundred newly-built green suburbs were originally envisaged. The competition was narrowed to twenty-five urban areas and, then, to just four. The final selections were Greenbelt, Maryland {outside Washington, DC}, Greenhills, Ohio {outside Cincinnati}, Greendale, Wisconsin {outside Milwaukee} and Greenbrook, New Jersey {outside New York City}. In mid-1936, the Greenbrook plan was dropped.

Rexford G. Tugwell, who was instrumental in the creation of America's green suburbs. Browbeaten by his conservative detractors, he resigned from his federal post in late 1936.
Photo from Wikipedia 

A photo-op groundbreaking was held in June 1935 at the Greenbelt, Maryland site. Land clearing was soon underway, with actual construction commencing in October 1935.
Photo from Library of Congress / Elmer Johnson