San Bernardino National Forest has two main divisions which are the San Bernardino Mountains on the easternmost of the Transverse Range, and the San Jacinto and Santa Rosa Mountains on the northernmost of the Peninsular Range. Covering more than 800,000 acres, with elevations that range from 2,000 feet to 11,502 feet, the forest includes five wilderness areas: San Gorgonio, Cucamonga, San Jacinto, Santa Rose and Bighorn Mountain. San Bernardino Mountains The San Bernardino Mountains are short transverse mountain range northeast of Los Angeles in southern California in the United States. ... The Transverse ranges are a group of mountain ranges of southern California, part of the North American Coast Ranges that run along the Pacific coast from Alaska to Mexico. ... North slope of San Jacinto Peak San Jacinto Mountains The San Jacinto Mountains are short mountain range east of Los Angeles in southern California in the United States. ... Santa Rosa Mountains The Santa Rosa Mountains are a short peninsular range east of Los Angeles and northeast of San Diego in southern California in the United States. ...