In the Postclassic Era many of the great nations and cities of the Classic Era collapsed , although some continued , such as in Oaxaca , Cholula , and the Maya of Yucatán , such as at Chichen Itza and Uxmal .
Many of the great nations and cities of the Classic Era collapsed , but some continue , such as in Oaxaca , Cholula , and the Maya of Yucatán , such as at Chichen Itza and Uxmal .