The American corillera consists of an essentially continuous sequence of mountain ranges that form the western "backbone" of North America, Central America and South America. From north to south, this sequence of overlapping and parallel ranges begins with the Alaska Range and the Brooks Range in Alaska and run through the Yukon into British Columbia. The main belt of the Rocky Mountains along with the parallel Coast Ranges of mountains and islands continue through British Columbia and Vancouver Island. In the United States, the Cordillera branches to include the Rockies, the Sierra Nevada, and the Cascades and Coast ranges of Washington, Oregon, and California. In Mexico, the Cordillera continues through the Sierra Madre Occidental and Sierra Madre Oriental, as well as the backbone mountains of the Baja California peninsula.