Mount Lemmon is a high mountain peak at an elevation of 2.792m (9,159ft) above the sea level, located in Pima County, north of Tucson, in Arizona, United States. This favorite of Arizona cyclists is known for its hill climb. It's one of the highest mountain roads of Arizona.
Nestled in the Santa Catalina Mountains, within the Coronado National Forest, the road to the summit is paved but pretty steep. It’s called Catalina Highway, General Hitchcock Highway, Sky Island Scenic Byway, Mount Lemmon Highway and Arizona Forest Highway 39. It’s 27 mi (43 km) long and was built in 1933. This road is usually open all year round. It’s a hors categorie climb that provides a rare combination of sustained climbing, excellent road surface, spectacular vistas, and importantly, an escape from the 100+ summer temps in Tucson. Paved and suitable for most vehicles. Very large motor homes, trailers over 22' and buses may have trouble negotiating steep grades and sharp turns. There are a few places to turn around.
It’s a difficult road, with uncountable turns and twists. Remember this is a mountainous area, climbing up a high mountain. The summit hosts an astronomical observatory which was formerly the site of a USAF radar base of the Air Defense Command. The peak receives 200 inches (508 cm) of snow annually. The summit of the mountain is approximately twenty degrees cooler than the base. Therefore, large amounts of snow fall during the winter months, making it a cool escape and popular tourist attraction for Tucson and Phoenix habitants. The peak was named after botanist Sara Plummer Lemmon.