The Southern Rockies & Colorado River Basin Regional Map - This map covers the central Mountain West from central Wyoming down into northern Mexico. It includes the westernmost high plains on the east, and a good deal of eastern Nevada and southeastern California on the west. Idaho’s Snake River Plain occupies the northwestern corner, and South Dakota’s Black Hills can be (barely) seen at the northeast. All of the Colorado / Green river system is shown, and most of the Rio Grande and Pecos.
The map includes all of Utah, Colorado, Arizona, and New Mexico; most of Wyoming; a lot of Nevada; and smaller portions of neighboring states.