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Two ancient cities lying at the bottom of Qiandao Lake were unveiled, enthralling the nation with their mystery and beauty.
From April 27 to May 1, China Central Television and Zhejiang Satellite Television jointly telecast an underwater exploration of the two cities. With reporters on site and an unmanned helicopter filming over the lake, the two television stations presented a three-dimensional view of the two cities to spectators across the country.
Beneath the serene water of Qiandao Lake(a lake with a thousand islands) lie the two ancient sites—Shicheng City and Hecheng City—a discovery that has since captured the imagination of observers.
Qiandao Lake, a gigantic man-made lake in Chun’an County of east China’s Zhejiang Province, is hailed as “the most beautiful waters under heaven.” It is home to 1,078 large islands and several thousand smaller ones scattering across it. The lake is a popular destination for people seeking a scenic spot.
Both cities have a history of more than a thousand years. Hecheng was built in 208 and the Shicheng was built in the current location in 621. Shicheng, the administrative center of the ancient Sui’an County, had many historic and scenic locales.
Archaic revival
“We found a lot of memorial arches, stone doors and stone lions. These stone structures were kept intact underwater,” said Zhang Shuheng, a senior research fellow with the Zhejiang Provincial Institute of Cultural Relics and Archaeology. “This is the most rewarding discovery since underwater exploration of the two cities was conducted in 2001,” he added.
In a recent two-day excavation, the team explored Ruxueqian, the cultural and education center of Shicheng. An underwater robot found millstones, walls, large square stones and a number of construction relics.
Their findings match known statistics about the city. According to historical records, there was a Confucian temple, a school, six memorial arches and an ancient cypress in the area. It once cultivated 84 successful candidates in the highest imperial examinations and 203 in the imperial examinations at the provincial level. It served as a symbol of the profound culture of the city.
Mysteries remain beneath the surface, yet to be discovered. Local resident Zhang Weizhao described one missing piece, “In 1959, there was an ancient bell dating from the Yuan Dynasty (1271-1368) on the north gate tower of Shicheng. It weighed 1,500 kg. During the War of Resistance Against Japan(1937-45), people rang the bell to warn the local residents of invading Japanese. This was recorded in detail in the county annals. But unfortunately the divers went down several times but still couldn’t find the bell.” Born in the 1960s, Zhang was one of the staff working on the live telecast. Although he didn’t personally witness Shicheng, a vivid picture of the city was carved in his mind by the stories his parents told him of its past.
It was a typical ancient city. With convenient land and water transportation, the city had five gates, each of which had a gate tower. Around the city walls were eight watchtowers. Historic and scenic spots stood within the walled compound, including pagodas built in the Ming Dynasty (1368-1644) and the Qing Dynasty (1644-1911), memorial arches, ancient bridges and ancient tombs.
Diving into history
Qiandao Lake is actually a reservoir. More than 50 years ago, it contained dense woods and vast valleys, with the Xin’an River running through it.
In 1959, the then-largest water control project—the Xin’an River Hydro-Electric Power Station—began construction to supply power to its six surrounding provinces in east China, facilitating irrigation and preventing floods.
On September 21, 1959, the power station started to dam the river and store water. As a result, more than 290,000 local residents were resettled. Within half a year, the reservoir area flooded the two ancient cities, three towns and 1,377 ancient villages.
The first underwater exploration of flooded ancient cities took place in 2001, when the Beijing Dragon Diving Club Ltd., began a diving project at one of the lake’s islands. Qiu Feng, an official of the local tourism administration, met them and asked the club to send divers to search for the remains of the underwater ruins.
On September 18, 2001, the exploration team began the first of many dives. “We were so lucky that the divers found the city walls and picked up a brick of it as soon as they went down,” said Qiu.
“During my eight years’ diving experience, the ancient cities were the most beautiful scene that I have ever discovered underwater,”said Liu Jinyong, manager of diving course of the club’s Qiandao Lake branch. “Every time I swam into the cities and saw the painted rafters and carved beams, I felt as if traveling through a time warp,” he said.
Remains of the city walls and gates were found about 30 meters beneath the water surface. They were the first to touch the submerged artifacts in more than 40 years.
Inside the ancient Shicheng City, the divers found wooden beams, stairs and brick walls of a number of houses still standing at the bottom of the lake. The surrounding walls of some larger houses were intact. Inside the houses, the painted rafters and carved beams remained visible. Thrilled by the discovery, Qiu immediately reported the find to the local government. Since then, the ancient sites have come into view of the public and have been attached much attention. Further explorations have been continuously carried out. Before the live broadcast, a total of five explorations had been done.
In 2002, a joint underwater exploration was conducted again. The exploration team used manned diving robots, sonar detection and other technologies.
In 2005, the exploration team found that in addition to the two ancient cities, there were three towns named Weipi, Gangkou and Chayuan beneath the water. Still intact, the newly rediscovered sites constitute a complete map of the historic area. This further increased the archeological value of the discovery.
In November 2009, Wu Lixin, a professional underwater photographer entrusted by the Chinese National Geography (CNG), an authoritative geographic magazine of China, started photographing the underwater cities and towns. He dove to the lake bottom four times and took stunning pictures.
In February 2011, CNG published a set of Wu’s photographs. The gallery once again aroused a wave of interest in the ancient cities across the country.
On January 7, 2011, the underwater Shicheng City was officially approved as a cultural relic under the provincial protection of Zhejiang.
Development attempts
The discovery that the underwater cities and towns were kept intact excited the local people. The development efforts have inspired debates in Chun’an, where Qiandao Lake is located.
Various proposals were brought forward, but very few were feasible, said Xu Xiangzhi, Deputy Director of the Qiandao Lake Tourist Administration.
Some suggested allowing tourists to dive down to the ancient sites, but the idea was immediately rejected because of the hazards for uncertified people in diving more than 7-8 meters below the lake’s surface. To reach the underwater ruins, they would have to plunge more than 20 meters down. Mud at the lake bottom was another potential safety hazard.
Others suggested moving the ancien structures out of water and restoring the ancient cities on land, as attempted in some cultural heritage protection projects. The local government countered that there wasn’t an area big or flat enough to house the original cities. Experts warned that the wooden buildings would easily decay after being removed from the water.
While these proposals were shot down in the discussion phase, a feasible solution was tentatively reached—underwater sightseeing by submarine. Hangzhou Green Century Tourism Development Co. invested 40 million yuan($6.35 million) to build China’s first inland river sightseeing submarine. With 48 seats, the submarine is capable of diving up to 50 meters below the surface.
Since its completion in 2004, however, the submarine has never made a trip. It was not approved by the government.
There was no example of a submarine being used in an inland river in China, and the Central Government had no regulations on the management of civilian submarines, said Chen Jiasheng, an official of the Hangzhou Port and Shipping Administration Bureau.
“Till now, China still has not established such regulations, and the submarine has never been put into use,” said Xu. Even if such regulations were formed and the submarine was approved for use, it still couldn’t fulfill its sightseeing purpose. The strong currents produced by the submarine would threaten to destroy the city walls and houses, Xu added.
Some people insist on leaving the underwater sites undisturbed to protect them.
Leaving the ancient cities untouched in their current condition is the best protection, said Fang Minghua, Deputy Director of the Press and Publication Bureau and former Director of the Cultural Relic Bureau of Chun’an.
It is still too early to tamper with the artifacts, as there are no mature technologies to keep them intact after removal from the water, said Fang. For instance, during an exploration, the divers carried two beams of a roof to the land. Soon after the water evaporated, the beams began to wither and dry up.
Past experience indicates the wooden structures should stay in place beneath the surface rather than attempting a full excavation.
The ultimate goal of cultural relic protection was to maintain its value for education, economic benefits or historical study. But the premise of making use of the relics depended first on protecting them, said Fang.
Archimedes bridge
With efforts to find a solution in a deadlock, a bold idea brought hope to the local peo- ple—building an Archimedes bridge across Qiandao Lake.
An Archimedes bridge, also called a suspended tunnel or submerged floating tunnel, is a tunnel that can float in the water. It is based on Archimedes law, from which the bridge gets its name.
When completed, the 100-meter-long bridge will be fully submerged in water. From the outside, it will look like an oval tube. Inside, there will be motorways in the middle and two railway tracks flanking them. The bridge is anticipated to be a promising architectural technique. Compared with similar techniques like suspension bridges and sunken tunnels, it is cheaper to build and it produces less pollution, said a report on the proposed project.
Though the technique can be widely used in places like straits and inland rivers, it has to overcome some technical problems.
The Sino-Italian cooperation culminated in a treaty signed in 2004 between the Institute of Mechanics of the Chinese Academy of Sciences (CAS) and the Italian Archimedes Bridge Co., which paved the way for future construction of the bridge.
This proposal was offered by the CAS, China’s leading academic institution and comprehensive research and development center in natural science, technological science and hi-tech innovation.
At the end of 2002, CAS President Lu Yongxiang visited Qiandao Lake and learned of the problems in developing the underwater cities. In July 2003, Institute of Mechanics of CAS proposed plans for the bridge to the Chun’an Government, and the two signed a cooperation agreement.
“At present, the simulation bridge has passed tests in the laboratory. The next step is to test it in a water environment similar to that of Qiandao Lake. Later we will conduct tests in Qiandao Lake,” said Fang Yang, Director of the Qiandao Lake Tourist Administration.
“If the bridge is completed successfully, the tourists can appreciate the ancient cities from inside the tunnel, with no harm to the cities,” said Xu.
Construction of an Archimedes bridge is a worldwide effort. Currently, seven countries are working on the technology, including Norway, Italy, Japan, China, Switzerland, Brazil and the United States. If the bridge in Qiandao Lake is completed successfully, it will be the world’s first Archimedes bridge.