Thurmont is a town in Frederick County, Maryland, United States. The population was 5,588 at the 2000 census. The town is located in the northern part of Frederick County, approximately ten miles from the Pennsylvania border, along U.S. Highway 15. It is very close to Cunningham Falls State Park and Catoctin Mountain Park, which contains the presidential retreat of Camp David. The town's slogan is "Gateway to the Mountains. " Thurmont was designated in 2005 as a "Main Street Maryland Community."