'Terrace of a royal city'

Since 2016, the site of the 80,000-square-meter Huangchengtai, or "the terrace of a royal city", has been the focal area of Sun's studies. The exquisitely designed gates and protective walls, as well as ruins of grand high-level architecture, showed its core role in Shimao.

About 40,000 relics made of jade, bronze, stone and bones, as well as pottery items, may compose a kaleidoscope for today's viewers to imagine the life of rulers in Shimao. Fragments of murals, pieces of silk and lacquerware are also enticing for researchers.

Discovery of the square architectural foundation, covering 16,000 square meters, is of the greatest significance on Huangchengtai. Though only the southern side of the foundation has been fully unveiled, as many as 70 stone reliefs of human faces, mythical animals or symbols were found.

"Currently, we're still unsure whether these statues were from a giant shrine and were moved to this foundation, which features 'a palatial city', after the original architecture got destroyed," Sun says. "It needs further study. But if so, it may reflect a huge social change among the upper class."

According to Sun, Huangchengtai is the best-preserved ruins of an early-stage palatial city in East Asia. But findings like the stone reliefs also vaguely portray a picture of a "holy city". As Sun adds, walls were built in Shimao not only for safety, they also stand for kingship and theocracy.

About 20 ceramic eagles and numerous bones used for oracles further indicate the exceptional status of Huangchengtai in a religious system. Separately, over 10,000 needles made of bones show that the site is an economic hub.