The archaeological complex of Niuheliang, is a collection of late Neolithic Hongshan culture sites in Chaoyang. Niuheliang covers an area of almost 50 square kilometers with at least sixteen separate localities including cemetery areas and altars. Recent excavations at Niuheliang led by Guo Dashun of the Archaeology Society of China have revealed an abundance of jade artifacts, lending support for the notion of a Jade Age between Stone and Bronze ages in the region.

(Source: archaeology.about.com)