An epic field survey aided by a range of high-tech devices will be carried out along China's 6,300-kilometer-long Great Wall, China Daily reports on Wednesday (Mar 15).

A group of heritage guardians will use laser range finders, global positioning system (GPS) devices and digital cameras to make detailed records, brick by brick, of the mammoth structure.

The field survey is part of the 10-year Great Wall Protection Project that kicked off last month, said Chai Xiaoming, deputy director of the Heritage Protection Department of the State Administration of Cultural Heritage.

The survey will take at least two years and involve hundreds of specialists, Chai said, adding that an overall protection plan for the structure is expected to be completed by 2009.

A massive repair program on the Wall, only one-fifth of which is considered well preserved, will follow the survey. Special patrol teams will also guard against further man-made damage of the Wall, the paper says.

"By 2014, when the overall project is scheduled to be finished, we will not only have a clear and complete picture of the current conditions of the Great Wall and its landscape, but also have a basic legal framework for its protection, such as marking out its preservation areas and buffer zones," the paper quotes Cai Xiaoming as saying.

At present, all the State-level heritage sites, except the Great Wall, have clearly defined preservation areas and buffer zones. The survey will help China control construction projects near the Wall.

Luo Zhewen, a renowned heritage expert, said the field survey will be "extremely arduous."

He said the central government had tried many times since the 1950s to find out the real conditions of the Great Wall, but attempts were never completed because of various reasons.

Editor: Wing