The Great Wall of China is famous for being the largest man-made structure in the world. It stretches some 1500 miles from end to end. Unfortunately, the Great Wall is now facing massive destruction from farmland expansion and construction.

Can you imagine that this is the most iconic monument in China? Under assault by expansion of farming activities, nearly two-thirds of China’s Great Wall may have been damaged or destroyed, while the rest remains under siege, says Li Lin from the China Great Wall Society.

"Definitely no segment of the wall is longer than one kilometer in rural areas. I myself never saw a wall longer than 100 meters during my field investigations on farmlands." Li said.

In Northwest China’s Gansu province, over 250 miles of the Great Wall can be seen on the map. It was first built in the Qin Dynasty about 2,200 years ago, and after 1,500 years, the Ming Dynasty rebuilt it. The Great Wall has survived nature’s decay for over 2,000 years. But the Great Wall is losing the battle with farmers living around, who have been turning it into pathways, cave shelters, or even fertilizers for the crops.

"The Great Wall was 10 to 15 meters high only decades ago. Now it hardly reaches 2 meters. The tiles we found there confirm its construction time and original patterns." Li said.

In 2006, the government released the Great Wall Protection Regulations and a 10-year protection project. However, the results are not as marked in rural areas as in tourism spots like Beijing. The Great Wall here has to give way to infrastructure construction.

"We tried to stop villagers from destroying the Great Wall. But the relics here are not included in the protection zone. Our hands are tied." Chen Jun with Longxi County Museum said.

Constructed by a succession of imperial dynasties, the network of barriers, towers and fortifications expanded over the centuries, as an attempt to defend imperial rulings.

At the height of its importance during the Ming dynasty, the Great Wall is believed to have extended some 4,000 miles, 10 times the distance from New York to Los Angeles.