Southern Arizona City is a term that refers to two cities in the region: Tucson and Yuma. Tucson is a 6-letter city located in the Sonoran Desert of Arizona, and is the second largest city in the state. It is known for its diverse culture, vibrant nightlife, and many attractions such as the Arizona-Sonora Desert Museum and Saguaro National Park. Yuma is a 4-letter city located in the southwestern corner of Arizona, near the California and Mexico borders. It is known for its hot desert climate and its proximity to the Colorado River.