Brad Mitzelfelt represents the largest county supervisory district in the contiguous United States. His district sprawls from Wrightwood in the San Gabriel Mountains to most of the Mojave Desert, from Lucerne Valley to the City of Twentynine Palms to Parker Dam and the City of Needles on the Colorado River, to Baker, the City of Barstow, Trona, and Red Mountain on the border with Kern County. He represents seven incorporated municipalities, including Adelanto, Apple Valley, Hesperia and Victorville in the Victor Valley.
The district borders the states of Arizona and Nevada and includes portions of Joshua Tree and Death Valley National Parks, the entire Mojave National Preserve, the Marine Corps Logistics Base Barstow, the Army’s National Training Center at Fort Irwin, the former George Air Force Base (now the Southern California Logistics Airport), and portions of the Marine Corps Air-Ground Combat Center Twentynine Palms, the Naval Weapons Center China Lake and Edwards Air Force Base.