The rise of social elites in China was accompanied by an increase in social control and violence as the abundance of arrowheads and evidence of massacres attest. One such massacre resulted in these bodies being thrown down a well.
As competition between communities increased, ditches around settlements were replaced by tamped earth walls made using a technique called 'hangtu' which was to become common in later China. Such walls began to appear around some of the settlements of the Longshan cultures after 3000 BC.
They were up to 45 ft (13 m) high and 35 ft (10 m) wide at the base and had entrances protected by gatehouses. These walls enclosed settlements of various sizes, from 3.5 ha at Pingliangtai to 17.5 ha at Chengziyai, which contained dwellings and workshops.
Some buildings were raised on tamped earth platforms. Humans, both children and adults, were sometimes buried between layers of tamped earth, perhaps sacrificed when the earthen foundations were laid.
