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.