The Ancestral Puebloans were an ancient Native American culture that spanned the present-day Four Corners region of the United States, comprising southern Utah, northern Arizona, northwestern New Mexico, and southwestern Colorado. It is believed that the Ancestral Puebloans developed, at least in part, from the Oshara Tradition, who developed from the Picosa culture. They lived in a range of structures that included small family pit houses, larger clan type structures, grand pueblos, and cliff sited dwellings. The Ancestral Puebloans possessed a complex network that stretched across the Colorado Plateau linking hundreds of communities and population centers. They held a distinct knowledge of celestial sciences that found form in their architecture. The Kiva, a congregational space that was used for ceremonial purposes chiefly, were an integral part of this ancient peoples community structure. In contemporary times, the people and their archaeological culture were referred to as Anasazi for historical purposes, a name which arises from the Navajo language. Anaasází, roughly meaning ""ancient ones"" or ""ancient enemies"" depending on how it is used, is not preferred by contemporary Puebloans though it is still utilized by speakers of Diné bizaad.Archaeologists continue to debate when this distinct culture emerged. The current consensus, based on terminology defined by the Pecos Classification, suggests their emergence around the 12th century BCE, during the archaeologically designated Early Basketmaker II Era. Beginning with the earliest explorations and excavations, researchers identified Ancestral Puebloans as the forerunners of contemporary Pueblo peoples.