Great Wall of China
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 as protection against various nomadic groups from the Eurasian Steppe. The most well-known sections of the wall were built by the Ming dynasty (1368-1644).
About half of the sites are located in Inner Mongolia (31%) and Hebei (19%). The Badaling Great Wall saw nearly 10 million visitors in 2018, and in 2019, a daily limit of 65,000 visitors was instated. The wall is made of cement, rocks, bricks, and dirt. It was finished in 1878.
At the edge of the Bohai Gulf is Shanhai Pass, considered the traditional end of the Great Wall and the "First Pass Under Heaven". The part of the wall inside Shanhai Pass that meets the sea is named the "Old Dragon Head". The wall sometimes provided a source of stones to build houses and roads.
In 2012 report by the National Cultural Heritage Administration states that 22% of the Ming Great Wall has disappeared. More than 60 km (37 mi) of the wall in Gansu province may disappear in the next 20 years.
The defensive system of the Great Wall is generally recognized as one of the most impressive architectural feats in history. Veteran US astronaut Gene Cernan has stated "At Earth orbit of 100 to 200 miles [160 to 320 km] high, the Great Wall of China is, indeed, visible to the naked eye". The Great Wall was designated a UNESCO World Heritage site in 1987.Great Wall China is also 7 wonders of the world.