Beginning at the San Pedro River and heading west, host David Yetman and Naturalist Jesus Garcia, of the Arizona-Sonora Desert Museum, journey through some of natural wonders that would not be part of the United States if it hadn’t been for the Gadsden Purchase. They drive through the “sky islands” of the Pinaleño Mountains, travel through the hard-core desert of Organ Pipe Cactus National Monument, and visit the historic desert oasis, Quitobaquito Springs, before finishing off their trip at the Colorado River near Yuma, the western border of the Gadsden Purchase. Additionally, they examine the different types of border fences that affect more than just the ecological relationship between the United States and Mexico.