The Chinese Pyramids: Xi'an's Flat-Topped Imperial Mounds

A wartime pilot banking over central China glances down and sees, so the story goes, an enormous pale pyramid rising from the plain, bigger than anything in Egypt, and no one back home will quite believe him. For decades afterward people ask why the giant Chinese pyramids were kept secret, and whether anything human built them at all. The plain answer is duller and stranger than the rumour.

The structures are real and they are numerous. Clustered on the Guanzhong plain around Xi'an, in Shaanxi province, are dozens of large earthen mounds, flat-topped and roughly pyramidal, built as the tombs of emperors and nobles across the Qin, Han and later dynasties. They were never hidden in any meaningful sense; they sit in a well-populated agricultural region, they appear in Chinese records, and local people farmed around them for centuries. What kept them out of Western consciousness was distance, politics and language, not concealment.

Tombs, not temples

These are burial mounds, engineered from rammed earth rather than cut stone, and their flat tops and broad bases reflect a different tradition from the Egyptian or Mesoamerican pyramid. The most famous belongs to Qin Shi Huang, the first emperor of unified China, who died in 210 BCE; his tomb mound stands near the pits of the Terracotta Army discovered in 1974, the clearest possible demonstration of what these structures are and who they served. Others, such as Maoling, the tomb of Emperor Wu of Han, are among the largest and are strong candidates for the great pale pyramid the wartime accounts described.

The white pyramid legend

The mystery is largely an import. In 1945 a US Army pilot, sometimes named as James Gaussman, was said to have reported a huge white pyramid capped with jewel-like material, and in 1947 a New York Times item relayed a similar sighting attributed to a Colonel Maurice Sheahan. Grainy photographs circulated. Later, ancient-astronaut writers seized on the mounds as evidence of extraterrestrial engineering, filing them alongside other supposed out-of-place artefacts and even weaving them into speculation about earth energies and ley lines. The sightings were real enough; what they saw was Maoling or a neighbouring imperial tomb, unremarkable to Chinese archaeologists and quietly documented for generations.

What the ground actually holds

Chinese authorities have deliberately left many of the mounds unexcavated, which fuels the secrecy story but reflects sound preservation policy rather than a cover-up: the technology to open a two-thousand-year-old tomb without destroying its contents is still developing, and the first emperor's tomb in particular is treated with caution. The ancient historian Sima Qian described that tomb as containing rivers of mercury flowing beneath a jewelled ceiling, and soil surveys have found genuinely anomalous mercury concentrations over the mound, a rare case of a fantastical old text lining up with a modern measurement.

The tidy account closes almost everything. What it leaves is the small, real puzzle of that mercury reading and an unopened chamber that no living person has entered, described only by a writer dead for two millennia. Nothing supernatural, but a sealed room the size of a hill that still keeps its own counsel.

Below, readers have filed their own encounters with hidden structures, official silences, and monuments that felt too large for their makers, voting each True, Fake or Not sure. Look down from the pilot's window and decide.