The mountain spines of the two American continents are discontinuous, belonging as they do to separate plates.
The Mexican range of the Rockies are the Sierra Madres, in Alaska the Brooks Range.
Each is composed of a number of named ranges, the Rocky Mts. having over 100, the Sierra Madres 2.

The Coast Range of the U.S. often includes the Sierra Nevada And the Alaska Range; The Cascades in part parallel the Coast Range.