Recreational Demonstration Area
The Recreational Demonstration Area program (also known as the Recreation Demonstration Area program) was a National Park Service program during the 1930s and early 1940s that built forty-six public parks in twenty-four states on 397,000 acres (1,606.6 km2), chiefly near urban areas in the United States. The NPS used labor from a variety of Great Depression federal relief programs, chiefly the Civilian Conservation Corps and Works Progress Administration, to build recreational demonstration areas.
Source: Wikipedia — Recreational Demonstration Area (CC BY-SA 4.0)