China needs 2 yrs to map Great Wall

Beijing: A 500-year-old question - just how long is the Great Wall?, would be answered in 2008 by two Chinese government departments.

China's State Administration of Cultural Heritage (SACH) and State Bureau of Surveying and Mapping (SBSM) will launch a massive geographical survey of the Great Wall.

The survey will be completed in 2007 and the basic statistics of the Great Wall, including its length and layout, will be released in 2008, officials said.

Local governments have been gathering statistics on the Great Wall since the 1980s.

"But due to limited knowledge and technology, much of the Great Wall is still a mystery," said SACH director Shan Qixiang.

"The government needs to organise a scientific survey so we can have a comprehensive and accurate understanding of the Great Wall," Shan said.

The departments will jointly establish a database based on the results of their survey to facilitate future research and protection of the Great Wall.

Parts of the survey have already started in Hebei and Henan provinces.

The Great Wall was first built in the Warring States Period (475-221 BC), when separate sections were built in various strategic areas to defend China against invasion by northern nomadic tribes.

A large portion of the Great Wall was located in poor, remote areas where few people reside. The traditional estimate of length was 50,000 li, or 25,000 km.

Scientists and historians say they will focus their work on the portion of the Great Wall that was built during the Ming Dynasty.

Records show that the Ming portion walls meandered through China's Liaoning, Hebei, Tianjin, Beijing, Shanxi, Shaanxi, Ningxia and Gansu province, autonomous regions and municipalities. The portion was estimated at 5,660 km.

However, experts have warned that only 30 per cent of the Ming portion walls are still standing.

Dong Yaohui, deputy resident of the China Great Wall Association, said less than 20 per cent of the Ming Great Wall is relatively well protected.

As nature and human activity continue to take their toll on the Great Wall, the Chinese government has increased efforts to protect the unique historical relic.

On Tuesday, the Chinese government issued a regulation to protect the Great Wall. The regulation bans vandalism and driving on the Great Wall, taking soil or bricks and building anything on it that is not designed to protect it.