Camp Greentop is located in Catoctin Mountain Park near Thurmont, Maryland. The camp was built by the Works Progress Administration labor program in the development of what was then known as the Catoctin Mountain Recreational Demonstration Area, and comprises 22 rustic log buildings including sleeping cabins, administrative buildings and lodges. All were built between 1934 and 1938. The buildings are a simplified version of the National Park Service Rustic style.