Archaeologists working at Chaco Canyon call these small villages "small house sites," and they call the large centers "great house sites." Small house sites usually have less than 20 rooms and were single-story. They lack big kivas and enclosed plazas are rare. There are hundreds of small sites in Chaco Canyon and they began to be constructed earlier than great sites.
Chaco Canyon has numerous kivas, below-ground ceremonial structures still used by modern Puebloan people today. Chaco Canyon's kivas are rounded, but in other Puebloan sites, they can be squared. The better-known kivas (called Great Kivas, and associated with Great House sites) were constructed between AD 1000 and 1100, during the Classic Bonito phase.