At 10,800 feet, San Jacinto is already in the rear-view mirror — climbed, conquered, and left behind. The PCT heads toward the San Bernardino Mountains and a resupply at Big Bear Lake. This is how Southern California is structured: the trail drops to a sweltering desert floor, then climbs back into air that burns in the afternoon and freezes before dawn — sixty degrees of swing from valley to ridge. The peaks are called sky islands — isolated alpine worlds, ringed by desert the way islands are ringed by sea.