17 days of pumping water out of the pond, a 'crazy' man suddenly discovered a wonder that surprised the world

Suspecting that the village fish pond was not natural and not as deep as the legend said, the man pumped all the water out of the pond and then the big secret was revealed.

The story happened in 1992 in the village of Shiyan Beicun , Longdu County, Zhejiang Province (China). A man named Wu Anai always had a hunch that the village's communal pond was not as deep as the villagers rumored. Because, before that, many generations of people living in Shiyan Beicun believed in a legend that this pond was infinitely deep, so no one dared to go near it. 

Mr. Wu did not believe it, so he mobilized some villagers to pump water out of the pond to prove to everyone that it was a normal pond. Together, they bought a water pump and worked tirelessly. After 17 days of pumping water, people were surprised to discover an ancient cave . From there, Mr. Wu also proved to everyone that his hunch was correct. Authorities and archaeologists were quickly called in to investigate.

Mr. Wu's seemingly foolish act led to the discovery of an incredibly massive ancient wonder.

This ancient cave was later named Long Du , after the administrative name of Long Du district. Through field surveys, archaeologists determined that Long Du is a system of artificial caves consisting of 24 small caves, each cave has an average floor area of about 1000m2 ^with a height of up to 30m. The total area of this cave system is about more than 30,000m2 ^. Typical caves have sloping roofs, supported by pillars.

Archaeologists have confirmed that this ancient cave system was entirely man-made based on the traces of chisel marks found around it. The chisel marks form parallel grooves that are believed to symbolize something.

Similar traces were also found on pottery (thought to have appeared between 500 and 800 BC) that is now stored and displayed in a nearby museum.

According to researchers, they were hand-carved out of muddy limestone. The discovery has attracted the attention of many experts from many countries around the world, including Japan, Poland, Singapore, and the United States.

In addition, there are many stairs, pillars and elaborate carvings in the cave system. However, one cannot rule out the possibility that the ancient people simply expanded a natural cave.

Long Du Cave may have been built 2000 years ago.

According to some archaeological experts, Long Du cave may have been built 2000 years ago.

Perhaps the only structure similar to the Longyou Caves is the Huashan Caves , but this structure is located 200km away, in another part of China, and may have been built up to 1,500 years later.

Preliminary estimates show that to complete this cave, people had to move nearly 1 million cubic meters of rock. According to scientists, the construction of Long Du cave required a huge human resource. The number of workers mobilized to create these 24 caves could be up to tens of thousands.

Everything about the origin and formation of Long Du remains a great mystery.

Such a large construction is often recorded in history books. However, there are almost no clues or information about it. Therefore, until now, everything about the origin and formation process of Long Du is still a big mystery. One of the most interesting and also the most difficult mysteries is why these 5 caves can maintain such an intact state for a period of more than 2,000 years.

Why the ancients went to such great lengths to create these caves is a mystery. Were they shelters, military bunkers, ceremonial structures, secret palaces for the elite, or mines for natural resources?

In 2014, researcher Yang Hongxun of the Institute of Archaeology of the Chinese Academy of Social Sciences proposed a hypothesis. Hongxun suggested that the caves were built by order of King Goujian of Yue in 494 BC. He argued that King Goujian used the Longyou Caves to hide thousands of his soldiers after a heavy defeat in battle. However, this hypothesis still fails to explain many other mysteries of the caves.