Prince William Forest Park was established as Chopawamsic Recreational Demonstration Area in 1936. Its location is in Triangle, Virginia, adjacent to the Marine Corps Base Quantico. The park is the largest protected natural area in the Washington, D.C. metropolitan region at over 16,000 acres (6,500 ha). Today, the park is a window into the past and serves as an example of what much of the East Coast once looked like centuries ago. The park serves as the largest example of Eastern Piedmont forest in the National Park System (arguably, one of the most heavily altered ecosystems in North America). The park also protects the Quantico Creek watershed. It is a sanctuary for numerous native plant and animal species.