Around 2300 BC, an enormous prehistoric ancient city was built along the Fen River in the south of Shanxi province. The site was home to an imperial graveyard, a palace, a residential district for noble houses, a residential area for ordinary people and a handicraft workshop area. People couldn't help associating it with Emperors Yao and Shun's capital described in legend. On the ceramic pot excavated there, two symbols written by cinnabar were considered the oldest Chinese characters known. A semi-circular relic was even considered the oldest observatory in the world. Wang Wei, director of Institute of Archaeology in Chinese Academy of Social Sciences, thought these discoveries dated the Chinese culture back 500 years further. Controversy over these conclusions is still on going.