This guidebook, prepared in conjunction with the 2008 joint meeting of the GSA Cordilleran and Rocky Mountain Sections, contains background information and road logs for eleven field trips in Nevada, Arizona, and California. Southern Nevada and adjoining areas contain a rich geologic history spanning the interval from the Paleoproterozoic to the present. Las Vegas lies at or near several critical geological junctures and localities including the structural boundary between the Colorado Plateau and Basin and Range, the physiographic boundary between the Great Basin and the southern Basin and Range, the eastern margin of the Sevier fold-and-thrust belt, the tectonically active Death Valley area, tilted and faulted volcanic-plutonic systems exposing the upper part of the crust, and the enigmatic “amagmatic zone.” With guides in this volume spanning the geologic record from the Ediacaran (late Neoproterozoic) to the Holocene, covering ground from the middle crust to the surface, and looking at topics from tectonics to paleontology, volcanism to glaciation, this volume offers something for everyone.