Complex sentence: Mount San Gorgonio rising above the basin on the west, the highest point in Southern California; and the Pacific Crest Trail passing through it and the San Gorgonio Wilderness area of the San Bernardino National Forest, between the peak and Morongo Basin.
Split into simpler sentences: Mount San Gorgonio rises above the basin on the west, the highest point in Southern California. The Pacific Crest Trail passes through the San Gorgonio Wilderness area of the San Bernardino National Forest, between the peak and Morongo Basin.