Mysteries of the Longyou caves
Phoenix hill, Shiyan Beicun, China: In 1994, an extremely mysterious discovery was made. Considered by the Chinese as the ninth ancient wonder of the world. A series of 24 ancient, artificial caves were discovered, specialists have been quietly astounded by them, and the more we learn, the more of a spectacular and mysterious achievement they are seen to be.
First discovered in 1992 by a local villager, 36 grottoes have now been discovered covering a massive 30,000 square metres. Carved into solid siltstone, each grotto descends around 30 metres underground and contains stone rooms, bridges, gutters and pools. There are pillars evenly distributed throughout the caves which are supporting the ceiling, and the walls, ceiling and stone columns are uniformly decorated with chisel marks in a series of parallel lines.
Despite their size and the effort involved in creating them, so far no trace of their construction or even their existence has been located in the historic record. Although the overall excavation involved almost a million cubic metres of stone, there is no archaeological evidence revealing where that quantity of stone went, and no evidence of the work. Moreover, there is not a single historic document that refers to them.
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