Near the village of Shiyan Beicun in Zhejiang province, some of the most fascinating underground constructions on the planet may be discovered. It’s no surprise that China considers it the world’s eighth wonder.

Examine the mysterious Longyou Caves in more detail.

As with many of the world’s great secrets, the Longyou Caves were discovered by accident. Bottomless wells and underground lakes have been rumored for years in the hamlet of Shiyan Beicun, where they are located.

The locals make use of the large quantity of fish in the groundwater to keep the mythology of endless ponds alive. One day, a man decided to check the veracity of this local legend to discover whether the underground constructions had a conclusion.

A large hydraulic pump was purchased with the as‌sistance of other members of the community, and all of the groundwater was pumped for 17 days in a row. Surprising hand-dug tunnels were discovered by chance, which was most likely the source of the water’s lack of bottom.

The pattern is massive and complex, and it’s full of mystery.

Following their discovery in 1992, these caverns were explored, revealing 30,000 square meters of caves and tunnels. The specialists were also awestruck by the beautifully constructed halls, chambers, bridges, ponds, and passages.

Concerns about this man-made grotto began to emerge, as one would expect. Who or what gave birth to it? What is the objective? Almost immediately, the search for written records from a Chinese emperor explaining the purpose of building this massive cave and how it was finished began.

However, no relevant documents have been found yet, at any time during any emperor’s reign. There have been no signs of workers, equipment, food, or even fish. The most fascinating feature of this underground building, though, is how it was built.

There is no trace of construction

The amount of time and human effort needed to construct such an intricate design, according to specialists who study man-made caves, must have been enormous. One million cubic meters of rock, for example, has been removed. The caves’ surroundings have yielded stone deposits and excavation remains, but not the caverns themselves.

More than 1000 workers are anticipated to be present to accomplish such a huge task, which would need chiseling and excavating for six years, 24 hours a day, seven days a week. This does not include the time spent drawing and delineating the cave’s sculptures, engravings, and reliefs.

Walls that have been meticulously crafted… by hand

In certain areas, the cave walls may reach a height of 30 meters. It features separate rooms, corridors, and gutters, as well as a distinctive chisel carving on every wall. The walls are carved with a hammer and chisel in a series of parallel lines from top to bottom. These marks are similar to those seen on pottery dating from 500 to 800 BC in a nearby museum.

Archaeologists and scholars are still puzzled by the exact location of its carvings, as well as the thickness of its walls.

“The ancient builders would not be able to see what the others were doing in the adjacent grotto from the bottom of each cave,” said Yang Hongxun of the Chinese Academy of Social Sciences (CASS). However, the interiors of each cave had to be parallel to one other, otherwise, the wall would have been breached during building. As a consequence, the measuring equipment needed to be very advanced. ‘I’m sure there was some forethought put into cave size, placement, and distances.’

How did these caves last so long without being altered?

In the area where the Longyou caves are located, earthquakes are very frequent. Inside, however, there are no signs of collapse, rubble piles, or damage to the walls or columns. Mountains and reliefs in the surrounding region have evolved in shape and size throughout time. However, everything remains the same inside the caves as it did the day before.

Tourists are now allowed to visit the caves for an $8 entrance charge.

How did the builders operate in the darkness of the caverns? Who built them, and why did they build them? How did they achieve such amazing accuracy without the use of technology or industrial equipment? These are just a handful of the many questions the Longyou Caves have presented to those who have studied them for years.