The Santa Catalina Mountains dominate Tucson's northern skyline. At 9,157 feet above sea-level, Mount Lemmon is the highest peak and perhaps Arizona's best known "sky island." It takes about an hour to drive to the top. The drive starts in beautiful saguaro-studded Sonoran Desert and winds up through oak and scrub desert then stunning rock formations before hitting a pine and fir forest. Along the way are spectacular views of the city below. Temperatures are usually at least 20 degrees cooler. At the top, is the small community of Summerhaven. A small ski resort, Ski Valley, offers a rare taste of winter – when there's snow.