A culture, river, and site in Chihuahua, northern Mexico. The town's name, Spanish for great houses refers to the extensive, multistoried ruins of a pre-Columbian town, which was probably founded in 1050 and burned around 1340, after which the abandoned valley lands were occupied by the Suma, who migrated in from the east. Ruins of this type are common in the valleys of the Casas Grandes and its tributaries. The earliest culture, also called the Viejo, was characterized by Mogollon-type pottery and pithouse dwellings. The following period, the Medio, had adobe houses. A third period, the Tardio, came after 1300 AD and was heavily influenced by Mesoamerica. The area was settled by the Spaniards in 1661/1662 and is now a national monument under the jurisdiction of the National Institute of Anthropology and History.