Greenbelt, city, Prince George’s county, central Maryland, U.S., a suburb of Washington, D.C. The original town was built between 1935 and 1937, when the first residents moved in, by the Federal Resettlement Administration as a planned community for middle-income families. Its name is descriptive of the parklike expanse that encircled it. Greenbelt is mainly residential—most of its original residents were government workers in Washington, D.C. In 1952 Greenbelt’s residents formed a corporation (cooperative) and purchased the federal government’s holdings. Subsequently new subdivisions were constructed in the surrounding area. Greenbelt Park (a unit of the National Park Service), the National Agricultural Research Center, and the NASA Goddard Space Flight Center are nearby. Inc. 1937. Pop. (2000) 21,456; (2010) 23,068.