China's Great Wall just got a little bit greater

The Great Wall of China is even greater than once thought.

A two-year government mapping study has uncovered new sections of the ancient Chinese monument that total about 180 miles, according to an official report.

Using mapping technologies such as infrared range finders and GPS devices, experts discovered portions of the wall – concealed by hills, trenches and rivers – that stretch from Hu Mountain in northern Liaoning province to Jiayu Pass in western Gansu province, China Daily reported yesterday.

The newly mapped parts of the wall were built during the Ming Dynasty (1368-1644) to protect against northern invaders and were submerged over time by sandstorms that moved across the arid region, the study said.

The additional parts mean the Great Wall, constructed 2,000 years ago to keep out Mongols and invaders, spans more than 4,000 miles.

Recent studies have shown that sections of the wall in Gansu are being reduced to "mounds of dirt" by sandstorms and may disappear entirely in 20 years. They blamed destructive farming methods in the 1950s that desertified large areas of northern China. China in recent years has begun restoring parts of the wall as well as trying to rein in commercial development on and around it.

Tourist encroachment has also been a problem in recent years, with state media saying that near Badaling almost every brick on a popular section of the wall has been carved with people's names or other graffiti. AP