The size of the Great Wall of China makes it one of the most impressive structures ever built. The total length is 8,851.8 km (5,500.3 mi). But the actual length of the wall is 6,259.6 km (3,889.5 mi) while the trenches are 359.7 km (223.5 mi). The entire length of the natural barriers is 2,232.5 km (1,387.2 mi).
The original walls were built to prevent Mongol nomads from getting into the country. The oldest walls were built during the Qin Dynasty (221-206 BCE) using stones, wood frames and earth. The next thousand years saw additions and fortifications being made. But it was during the Ming Dynasty (1388-1644 CE) that the contemporary walls were built.
The Ming Walls
The Ming walls were created in other places away from the Qin walls. The walls were 15 to 30 feet (4.6 to 9.1 meters) wide at the bottom and 9 to 12 feet (2.7 to 3.7 meters) wide at the top. They reached a height of 25 feet (7.6 meters) high. The dimensions of these walls were chosen to accommodate wagons and soldiers. Towers and guard stations were added later.
Despite the size of the Great Wall of China, it was only during the 17th century that Westerners began hearing about it. The site would eventually attract tourists. Sensing its tourism potential, the government began renovating the site.
By 1987 the wall was recognized as a World Heritage Site. The most popular portion is 50 miles (80 km) from Beijing. This portion of the structure gets thousands of visitors every day.
The North Pass, also known as Badaling, used to have several guards whose purpose was to protect Beijing. This area of the Wall is 5 meters (16 ft) wide and 7.8 meters (26 ft) high. The Jiayuguan West Pass is the Wall’s western edge.
One of the most striking areas is the steep slopes of the Ming Wall. It is 5 to 8 meters (16–26 ft) high and 1 kilometer (6.8 mi) long. Across the bottom it is 6 meters (20 ft) across. Along the top it narrows down to 5 meters (16 ft) across. There is also the Wangjinglou watchtower, rising 980 meters (3,220 ft) over the sea.
The size of the Great Wall of China is such that it can be seen while at low orbit of the planet. Despite what the legends say however, the wall cannot be seen from the Moon.