is the country retreat for the president of the United States. It is located in the wooded hills of Catoctin Mountain Park, in Frederick County, Maryland, near the towns of Thurmont, and Emmitsburg, about 62 miles (100 km) north-northwest of the national capital city of Washington, D.C. It is officially known as the Naval Support Facility Thurmont
. Because it is technically a military installation, the staffing is primarily provided by the Seabees, Civil Engineer Corps (CEC), the United States Navy and the United States Marine Corps. Naval construction battalions are tasked with base construction and send detachments as needed.