Mountain system in North America, extending from the Coast Mountains of Alaska and British Columbia, through Washington, Oregon, and California, to Baja California in northwest Mexico, and running almost parallel to the Pacific coast. The mountains of the Coast Ranges are very irregular in height and geological structure, with a number of peaks rising to 2,000 m/6,600 ft; while in the St Elias Mountains of the Yukon is the second highest peak in North America, Mt Logan (6,050 m/19,850 ft). In some places, especially the south, the mountains are almost bare, while in other places they are densely covered with forests. To the south, the ranges are subject to occasional earthquakes.
In British Columbia the Coast Ranges are represented by a chain of offshore islands, such as Vancouver Island. In Washington the mountains are called the Olympic group and are very rugged; the highest peak, Olympus, is 2,428 m/7,966 ft. The range diminishes in size in Oregon, averaging between 1,225 and 1,550 m/4,019 and 5,085 ft in most parts. In California the Coast Ranges consist of a series of low ranges broken by deep valleys, ending in the south at the Los Angeles lowland. Many of the trees on the slopes of the Coast Ranges grow to an enormous height (Douglas firs often reach a height of 80 m/262 ft). The forests in California contain the world's tallest trees, the sequoia and the redwood.