In the mid-17th century, the Manchus from central and southern Manchuria broke through the Great Wall and encroached on Beijing, eventually forcing the fall of the Ming dynasty and beginning of the Qing (Manchu) dynasty (1644-1912). Between the 18th and 20th centuries, the Great Wall emerged as the most common emblem of China for the Western world, and a symbol both physical–a manifestation of Chinese strength–and psychological–a representation of the barrier maintained by the Chinese state to repel foreign influences and exert control over its citizens.Today, the Great Wall is generally recognized as one of the most impressive architectural feats in history. In 1987, UNESCO designated the Great Wall a World Heritage site, and a popular claim that emerged in the 20th century holds that it is the only manmade structure that is visible from the moon. Over the years, roadways have been cut through the wall in various points, and many sections have deteriorated after centuries of neglect. The best-known section of the Great Wall of China–Badaling, located 43 miles (70 km) northwest of Beijing–was rebuilt in the late 1950s, and attracts thousands of national and foreign tourists every day.
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