China is measuring the 6000-km-long ?Great Wall? once again, using hi-tech measurement equipments. The first phase of the re-measuring of the Great Wall, one of the seven wonders of the world, started in north China?s Hebei province. It is the first time that China is making a precise measurement and accurate survey on the Great Wall with comprehensive investigation and mapping skills.

China has launched the nation-wide investigation of the Great Wall for twice since the establishment of the new China in 1949. In the mid-1950s, China did primary investigation on its age and distribution with the help of the national cultural relic survey and the second-time investigation was undertaken in the 1980s.

As the key task of China?s Great Wall Protection Project in the next several years, the investigation this time will cover the entity of the Great Wall, relative relics and sites, and resources so as to provide references for its protection. Its exact length is still suspending although it is normally dubbed ?Ten-thousand-mile Great Wall?.

By applying the remote sensing technology, geographic information system and the global positioning system, scientists hope to obtain authoritative statistics about the length of the Great Wall.