Location: Phoenix Hill, Zhejiang Province , China. Grid Reference: 29ï¿½ 2' 7" N, 119ï¿½ 10' 58" E. Longyou Grotto's: (Hand-Carved Caves). The Longyou Caves were only discovered late in the 20th century. At least 24 caves have been discovered so far. All of which were carved by hand. Although the overall excavation involved almost a million cubic metres of stone, there is no historical record of them or evidence of the work. Their origin is a complete mystery. At present there is no explanation for their existence. They represent one of the largest underground excavations of ancient times. They are considered by Chinese to be the 'Ninth Wonder of the Ancient World' The Longyou Caves: (Grotto's) The 'Mystery of a Thousand Years'. In June, 1992, a villager named Wu Anai, decided to pump the water out in one of the locally known caves revealing the first of many man-made caves in the region. After 17 days pumping, enough water had been removed to reveal the cave including several carved stelae, thus confirming his idea that they were not natural reservoirs at all, but rather man-made. The floor of the grotto occupies more than 2,000 square meters, with the tallest point of the cave exceeding 30 meters. The four steles of cave 1 are symmetrically distributed. Following this discovery, he continued to pump out another four caves only to find that they all bore the same markings on the walls and ceilings. A rough estimation of the workload involved in building these five caves is awe-inspiring. The four caves cover an average floor surface of 1,200 square meters, so each of the caves should have involved excavation of 36,000 cubic meters of stone. Since a total of at least 24 such caves have already been found in Shiyanbei Village, the overall excavation would be 900,000 cubic meters. (1) The chiselling on the cave walls and ceilings was executed in such a way that it has left them covered in a uniform pattern which some people believe is symbolic. It is similar to pottery found in the nearby museum which is dated between 500 and 800 BC. It is said that among them are seven caves whose distribution pattern resembles that of the seven stars of the Big Dipper. (2) In Cave 1, which has been opened for tourism, stone carvings executed in a craftsmanship of ancient simplicity, of horse, fish and bird, may be seen (Land, Water and Air). The bird head has an appearance similar to one unearthed at the Hemudu site. (2) Like most villages in southern China, there are numerous ponds in Shiyanbei, but these are mostly rectangular, and very deep, having been known as "bottomless ponds" by generations of villagers. These ponds teem with fish, which are easily caught. After the first cave was pumped dry not a single fish was to be seen. (2) This discovery has called the attention of many specialists from China, Japan, Poland, Singapore and USA. One of the most interesting and challenging questions is how the caverns have been able to keep their integrity for more than 2000 years. (3) Longyou: Gallery of Images. (Other Underground Sites) (China Homepage)