CASTLE CANYON. Castle Canyon, a valley that runs along the last two miles of Evans Creek, begins a mile west of U.S. Highway 90 in southern Val Verde County (at 29°32' N, 101°06' W) and runs southeast to its mouth on the north shore of Amistad Reservoir, one-half mile east of the Southern Pacific Railroad tracks (at 29°32' N, 101°04' W). The path of the arroyo sharply dissects massive limestone to form vertical cliffs. Wash deposits of gravel, sand, clay, and silt cover the floor. The area's flat to rolling prairies are surfaced by generally dark, calcareous stony clays and clay loams that support oaks, junipers, grasses, and mesquites. The canyon was named for the castle-shaped cones carved from its limestone walls by water erosion. In the 1880s a railroad station was located on Castle Canyon.