HUANGHUACHENG, China - The Great Wall of China is greater than previously thought, according to a recent technologically advanced survey of the World Heritage site.
China's most thorough investigation of the wall to date has shown that in the Ming Dynasty era, it stretched 8,851.8 km (5,500 miles), further than the previous estimate of around 6,000 km (3,700 miles).
According to the joint survey by the State Administration of Cultural Heritage (SACH) and the State Bureau of Surveying and Mapping, the massive structure is comprised of 6,259.6 km of wall, 2,232.5 km of natural barriers such as rivers and mountains, as well as 359.7 km of trenches.
Chen Jun, president of the National Geomatics Center who helped map the wall in three-dimensions for the survey, said the findings were important to the future of the wall, one of China's most famous symbols.
"This is significant because the Great Wall is like a name card for the Chinese people. People who have never come to China all know the Great Wall," Chen said.
"If we know how long the wall is and where it is located then we can protect it properly. So it really is very important."
Chen and other researchers spent over two years surveying the wall, using GPS positioning systems, infrared technology and other mapping techniques, to