Built as a defensive barrier to keep invaders out, the Great Wall of China's once formidable reputation crumbled away on Monday as a huge section of the structure collapsed.
Bungling workmen digging up a square at the foot of the wall have been blamed for triggering the disaster at Zhangjiakou, in Hebei province of northern China.
Locals also say a recent deluge of rain and additional major roadworks in front of the walls may have been a factor in causing the 100ft section to fall away in the early hours of the morning.
A city official said: 'There is an investigation into the causes of the collapse. A number of things may have contributed, including the building work.
'But we have a conservation and rebuilding plan and it is already underway.'
The original Great Wall dates back to seventh century China, but the section in Zhangjiakou was rebuilt more than 500 years ago in 1484 during the Ming Dynasty.
The wall has been constantly rebuilt and repaired throughout history. An expert said: 'Like any building project, some work lasts longer than others.'
Still one of the only man made objects visible from space, the wall is made of stone, brick, tamped earth, wood, and other materials.
It was built along an east-to-west line across the historical northern borders of China in part to protect the Chinese Empire against attack by various nomadic groups or military incursions by various warlike peoples or forces.
Sections of the Wall north of Beijing and near tourist centres have been preserved and even extensively renovated but in many locations the Wall is in disrepair.
In poorer parts of the country the Wall is sometimes used as a village playground or is used as a source of stones for rebuilding houses and roads.
Sections have also been affected by graffiti and vandalism. Other Parts have been destroyed to make way for construction.
More than 37 miles in the Gansu province may disappear in the next two decades, due to erosion from sandstorms.
In parts, the height of the wall has been reduced from more than 16ft to less than six feet.
The iconic square-shaped lookout towers that form the most famous images of the wall have disappeared completely.
Many western sections of the wall are constructed from mud, rather than brick and stone, and are therefore more susceptible to erosion.
In addition to acting as a shield against border enemies the Great Wall was also used to enforce duties on goods transported along the Silk Road, to regulate or encourage trade and control immigration and emigration.
Troop barracks, garrison stations, signaling capabilities through smoke or fire also helped to enhance the walls defensive characteristics.
The Wall goes from Shanhaiguan in the east, to Lop Lake in the west, an area that loosely represents the southern edge of Inner Mongolia. The entire length, which includes trenches and natural barriers such as hills and rivers, stretches to 5,500 miles.
Although other experts have concluded that if branches of the wall are included its entire length is around 14,000 miles.
The first wall construction is thought to date from the 7th century BC. Especially famous is the wall built between 220–206 BC by the first Emperor of China, Qin Shi Huang.
Little of that wall remains. Since then, the Great Wall has on and off been rebuilt, maintained, and enhanced; the majority of the existing wall was reconstructed during the Ming Dynasty in the 15th century./dailymail.co.uk/