The Catalina Highway, officially the General Hitchcock Highway, is the popular name for a Forest Highway and scenic route located in Pima County in southern Arizona. Also known as the Sky Island Scenic Byway, the Mount Lemmon Highway and Arizona Forest Highway 39, the Catalina Highway is the only paved roadway providing access to the resort village of Summerhaven as well as various recreational and scientific facilities located near the summit of Mount Lemmon. Ascending from the desert floor in Tucson to near the summit of Mount Lemmon, the short highway gains over 6,000 ft (1.8 km), showcasing a variety of climates ranging from lowland desert to alpine forests. The name sky island comes from the analogy of these mountains being like islands of forest in a sea of desert. It is designated as a scenic byway by the National Scenic Byways Program.