The Appalachian National Scenic Trail is a public footpath that follows more than 2,100 miles of Appalachian Mountain ridge lines between Maine and Georgia. It was designed, constructed, and marked in the 1920s and 1930s by volunteer hiking clubs brought together by the Appalachian Trail Conservancy, formed in 1925. The Cumberland Valley Appalachian Trail Club oversees the local section, which runs approximately 17 miles through the Cumberland Valley, passing between Blue Mountain and South Mountain and crossing the valley along Ironstone Ridge. The Appalachian Trail Conservancy's Mid-Atlantic Regional Office, located in Boiling Springs next to the lake, coordinates and oversees management and maintenance of the trail from northern Virginia to southern Connecticut and is the only one of the four regional offices actually located on the trail. The office occupies a building originally built as a restaurant for the trolley park that operated there in the early 1900s, and the one-acre property includes a gazebo built as a reminder of the area's park days. In 1991 the trail was re-routed to pass by the scenic lake and the site of the historic Carlisle Iron Works. In 2010 Boiling Springs was designated the first Appalachian Trail Community in Pennsylvania in recognition of its efforts to welcome hikers, protect the trail experience, and embrace the trail as a major community asset and recreation gateway for visitors from around the world.