Western Mexico

The Western Mexico is a region of United Mexican States formed by the states of Nayarit, Jalisco, Colima, and Michoacán, and including the Revillagigedo Islands, Marías Islands, and several smaller islands. The region extends from the coastal plain of the Pacific Ocean, the Sierra Madre Occidental, the Volcanic axis, the basin of Balsas River, the Sierra Madre del Sur and the southwest of the Mexican Plateau.