This volume, prepared as part of the Geological Society of America Annual Meeting in Phoenix, includes field guides covering aspects of the spectacular geology of southwestern North America. Field guides tackle the geology of the southern Colorado Plateau, from paleoenvironments of Petrified Forest National Park, to Jurassic sand dunes of southern Utah, to the San Francisco Volcanic Field, to awesome Grand Canyon. Appropriately for the 50th anniversary of the first lunar landing, one trip visits sites in northern Arizona that helped prepare astronauts for their missions. Several guides address aspects of the Proterozoic to Cenozoic tectonic development of the Transition Zone between the Colorado Plateau and the Basin and Range. Exploring the Basin and Range, guides feature Laramide tectonism and ore deposit development, features associated with large-magnitude Cenozoic extensional tectonism, large Miocene volcanic centers in northwestern Arizona, and tectonism and development of the lower Colorado River. Three field guides explore various aspects of northwestern Mexico, including tectonics and ore deposits of Sonora, fauna and paleoenvironments of Colorado River delta deposits, and volcanism in central Baja California. Finally, a guide analyzes anthropogenic earth fissures that have developed in the Phoenix metropolitan area.