The moment
Between about 850 and 1150 ancestral Pueblo people built great houses such as Pueblo Bonito, with more than 500 rooms, and huge round great kivas for ceremony, in a dry canyon in New Mexico. Roads ran out for hundreds of kilometres to outlying communities, buildings and rock carvings tracked the sun's yearly path, and scarlet macaws were brought from Mexico. Only a few thousand people lived in the canyon; many scholars see it as a ceremonial centre.