SANDSTONE MOUNTAIN. Sandstone Mountain stands 3½ miles southeast of Llano in central Llano County (at 30°44' N, 98°37' W). At an elevation of 1,385 feet, the summit rises 380 feet above the Llano River. Local topography ranges from flat to rolling to steep, locally dissected and covered with soils that vary from shallow and stony to sandy and clay loams. Vegetation consists primarily of open stands of live oak and mesquite.