The Great Wall of China

One of the few manmade objects that can be seen from outer space with the naked eye, the Great Wall of China is a series of fortifications that were built across the historical northern borders of ancient Chinese states and Imperial China, built as protection against various nomadic invaders from the Eurasian Steppe.

When was the Great Wall of China Built?

Several walls were built as early as the 7th century BCE, during the time of the Warring States period between the states of feudal lords. After Qin Shi Huang unified China from 220 to 206 BCE, the first emperor of China connected previously standalone walls into a unified defensive barrier.

Today, little of the Qin wall remains, however many successive dynasties built multiple stretches of border walls, which reached its peak during the Ming dynasty of 1368 to 1644, which saw the construction of 5,500 miles of walls, trenches and natural defensive barriers such as hills and rivers.

Beyond its role as a blockade against foreign invaders, the Great Wall also acted as border control, which allowed for the imposition of duties on goods transported along the Silk Road. It also became a safe corridor for the transportation of goods, while imposing a physical barrier for the control and management of immigration and emigration.

The Great Wall Today

While portions north of Beijing have been preserved and extensively renovated, in many other locations the Wall has fallen into disrepair. Over the intervening centuries since its original purpose, the Wall has been a source of stone in the construction of houses and roads, while other parts of the Wall have been defaced by taggers and vandals.

A 2012 report by the National Cultural Heritage Administration indicates that 22% of the Ming Great Wall has disappeared, which equates to 1,219 miles of once majestic, serpentine construction. The report further suggests that 37 miles of the wall in Gansu province may disappear over the next 20 years due to sandstorm erosion.