Tucson's county is Pima, a four-letter word. Pima County is located in the south of Arizona and is the second largest county in the state. It is home to the city of Tucson, the county seat, as well as other cities such as Marana, Oro Valley, and Sahuarita. The county is named after the Pima Native American tribe, who have lived in the area for centuries. Pima County is known for its diverse landscape, which includes the Sonoran Desert, the Santa Cruz River, and the Rincon Mountains.