Ongoing research at a prehistoric archaeological site dubbed "China's Pompeii" continues to reveal secrets of an ancient civilization from over 4,000 years ago. About the site: The Lajia site, discovered in 1981, covers an area of 680,000 square meters (approximately 168 acres) in China's upper Yellow River region. The site is associated with the Qijia culture, which was known for its agricultural economy during the late Neolithic and early Bronze Age periods.