Archaeologists have unearthed a number of pottery drain pipes at a Neolithic site of Longshan Culture dating back more than 4,000 years and believe they form China's earliest and most complete urban drainage system. The city drainage system was excavated in the Pingliangtai Ancient City ruins in central China's Henan Province. "The pottery pipes were connected with drainage ditches in the city," said Cao Yanpeng, associate research fellow with the Henan Provincial Institute of Cultural Relics and Archaeology.
Discovered in 1980, the Pingliangtai ruins were once a regional center in the Longshan Culture. A lot of cultural relics, including delicate jade ware and pottery were excavated there, Cao said.