Longyou Grottoes: 2.5 million tons of rock vanished with zero historical records. Discovered 1992 by farmers draining ponds in Yu Jang province, eastern China 24 caverns discovered, each roughly 1,000 sq m with ceilings up to 30 m high Total excavated area approximately 30,000 square meters

Discovered 1992 in eastern China: 24 caverns (now 36 known), each roughly 1,000 sq m with ceilings up to 30 m high. Workers removed an estimated 1 million cubic meters of rock - equivalent labor to major Egyptian pyramids. Consistent chisel marks everywhere. Rock simply vanished. No records mention the project. Dated to more than 2,000 years old.

Key facts claimed:

- Discovered 1992 by farmers draining ponds in Qujiang District, Zhejiang province, eastern China (not Yu Jang)

- Originally 24 caverns discovered, now 36 known, each roughly 1,000 sq m with ceilings up to 30 m high

- Total excavated area approximately 30,000 square meters

- An estimated 1 million cubic meters of rock removed (2.5 million tons)

- Would require 1,000 workers operating 24/7 for 6 years to complete

Key Facts

  • Discovered 1992 by farmers draining ponds in Yu Jang province, eastern China
  • 24 caverns discovered, each roughly 1,000 sq m with ceilings up to 30 m high
  • Total excavated area approximately 30,000 square meters
  • An estimated 1 million cubic meters of rock removed (2.5 million tons)
  • Would require 1,000 workers operating 24/7 for 6 years to complete
  • Roughly equivalent to major Egyptian pyramid construction in labor scale
  • No single historical record of the project exists in Chinese records
  • Chisel marks cover every wall and ceiling with consistent angle and spacing
  • Uniformity indicates centralized organized workforce with shared instructions
  • Each cave is identical with single entrance, vertical shaft with carved staircase
  • Drainage system at base to manage water inflow
  • No mounds of rubble found anywhere near the site
  • Rock simply vanished with no evidence of disposal or use in nearby construction
  • Tentatively dated to Qin dynasty but age remains unknown
  • Purpose completely unknown - theories include grain storage, military shelter, ceremonial use, resource extraction
  • No archaeological evidence supports any proposed theory

Related site: Longyou Grottoes — view location, images, and history on the Ancient Nerds map.

Source: Someone Built Underground Cities We Can’t Explain by Michael Button