Editing Pecos Classification (section)

===Pueblo II Period (900 – 1150)=== 
{{main|Pueblo II Period}}

By AD 1050, [[Chaco Canyon]] (in present-day [[New Mexico]]) was a major regional center, with a population of 1,500–5,000 people. It is surrounded by standardized planned towns, or ''great houses'', built from the wood of more than 200,000 trees. Thirty-foot-wide ({{convert|30|ft|m|disp=output only}}) [[road]]s, flanked by [[berm]]s, radiate from Chaco in various directions. Small blocks of above-ground masonry rooms and a kiva make up a typical [[pueblo]]. Great kivas were up to {{convert|50|-|70|ft}} in diameter.  Pottery consists of corrugated gray bisque and decorated black-on-white in addition to some decorated red and orange vessels. The people imported shells and [[turquoise]] from other cultures through trading.

During the 12th century, populations began to grow after a decline at the end of the [[Pueblo II Era|Pueblo II Period]].  More intense [[agriculture]] was characteristic, with [[terrace (agriculture)|terracing]] and [[irrigation]] common.