The National Park Service (NPS) is an agency of the United States federal government, within the United States Department of the Interior. The service manages all national parks; most national monuments; and other natural, historical, and recreational properties, with various title designations. The United States Congress created the agency on August 25, 1916, through the National Park Service Organic Act. Its headquarters is in Washington, D.C., within the main headquarters of the Department of the Interior.