PACKSADDLE MOUNTAIN (Brewster County). Packsaddle Mountain is fourteen miles northeast of Terlingua in southwestern Brewster County (at 29°31' N, 103°34' W). Its summit, at an elevation of 4,656 feet above sea level, rises some 1,180 feet above State Highway 118, just to the east. The mountain consists of inclined light-colored beds from the Cretaceous period, between 66 million and 144 million years old, surrounding a dark-colored core of intrusive igneous rock. The local soils are shallow and stony and support scrub brush and grasses.