Part of the Jemez Mountains, Valles Caldera, 14 miles (23 kilometers) in diameter, is a severely eroded volcano that shows the classic radial drainage pattern normally associated with composite volcanoes. Redondo Peak [11 254 feet (3430 meters)], its large dome, was formed in the middle of the caldera by the resurgence of the caldera floor. Several smaller, circular lava domes are discernible toward the northern edge of the caldera. The deep canyon along the southern flank allows the Jemez River to drain the caldera, whose floor shows some snow accumulation. The deeply eroded canyon east of the caldera is part of the Rio Grande Rift Valley.