Heart of Hongshan still beats

On the green hills of western Liaoning province, a newly excavated platform has revealed that Hongshan people could determine true north and south with remarkable precision 5,600 years ago.

This Neolithic culture tracked the sun's shadow with a vertical pole — a technique known as gui biao ce ying that would become fundamental to Chinese astronomy, surveying and urban planning.

The conclusion comes from Platform No 2 at Locality 1, the northern section of the Niuheliang site in Chaoyang, Liaoning, that was discovered in the 1980s. It is the most important ceremonial center of Hongshan culture that flourished in northeastern China from around 6,500 to 4,800 years ago, spanning parts of what is now Liaoning and Hebei provinces, as well as the Inner Mongolia autonomous region.

Renowned for its sophisticated jade craftsmanship and monumental ritual architecture, Hongshan is widely regarded as one of the earliest foundations of Chinese civilization beyond the Yellow River heartland.

The platform is a rectangular structure measuring 64.61 meters north to south and 41.39 meters east to west, one of nine such platforms that archaeologists identified in 2021 as a massive architectural complex at the site.

Its builders used a mix of earth and stone — compacted soil on flat ground, large stones topped with gravel in low-lying areas — a method that combined durability with drainage. The platform sits slightly north of the center of the complex.

The discovery is the latest in a series of findings that have transformed the site from a burial ground into what scholars now recognize as the ritual capital of an early Chinese state, complete with temples, altars, elites' tombs and a north-south axis that echoes that of Beijing.

Feng Shi, an academician of the Chinese Academy of Social Sciences, says the platform's precise north-south alignment reflects mastery of the er sheng system — two perpendicular reference lines running north to south and east to west.

According to Feng, shadow-measuring techniques date back at least 8,000 years.

Clear evidence of the system appears on pottery at sites dated 7,000 years ago, like Liulinxi in Hubei province. By 6,500 years ago, the Xishuipo site in Henan was already laid out along a meridian line. Niuheliang's Platform No 2, he says, is a direct application of this ancient astronomical tradition.

Yet, it lacks what many would consider an essential feature of a capital — city walls.

Guo Dashun, honorary director of the Liaoning Provincial Institute of Cultural Relics and Archaeology, points out that walls are not, in fact, essential.

Yinxu, the last capital of the Shang Dynasty (c.16th century-11th century BC), had no known city walls. Neither did Erlitou, widely regarded as a capital of the Xia Dynasty (c.21st century-16th century BC).

"Yet both are widely recognized as capitals," Guo says.