Two prehistoric city sites have been discovered at the Puchengdian ruins in Henan province. One of them has already been determined by archeologists to be more than 4,000 years old and belonging to the Longshan culture or late Neolithic cultures (3000 B.C.- 1700 B.C.).

　　The older city covers an area of more than 16,000 square meters, with the east, west and south walls still existing.

　　A well-preserved 5,000-year-old pottery kiln, comprised of a chamber, fireplace, workshop and ash pit was unearthed in the relic city site. Archaeologists say this is the first ancient kiln found in China.

　　Archaeologists acknowledged that the discovery of the primordial city offers rare material evidence for people to study the living habits and social organizations of the ancient society.