mountain and desert region in southern Arizona, U.S. The park—consisting of two districts, Saguaro West and Saguaro East, separated by the city of Tucson—embraces forests of saguaro: a giant candelabra-shaped cactus that may reach 50 feet (15 metres) in height and live for 150 to 200 years. Established as a national monument in 1933, it became a national park in 1994; it has a total area of 143 square miles (370 square km).

The saguaro, which is unique to the Sonoran Desert in the southwestern United States and northwestern Mexico, bears a white blossom (the Arizona state flower) and edible crimson fruit; holes in its trunk and branches excavated by Gila woodpeckers and gilded flickers serve as nesting places for wrens, owls, and other small birds. The relatively lush Sonoran Desert, with its summer midday temperatures of more than 100 °F (38 °C), is also home to other succulent cacti (chollas, prickly pears, bisnaga) and paloverdes, mesquite trees, and ocotillos. Animal life includes peccaries, kangaroo rats, Gila monsters, desert tortoises, rattlesnakes, and quail. The western section of the park includes part of the granite Tucson Mountains. The larger eastern section of the park rises to the Rincon Mountains in the east, where fir and juniper are found at higher elevations. There are scenic drives through saguaro forests in each section of the park.