With the new discovered sections, the total length of the Great Wall is around 3,900 miles.

The Great Wall of China is even greater than once thought, after a two-year government mapping study uncovered new sections totalling about 180 miles, according to a report posted on the website of the country’s national mapping agency.Using infrared range finders and GPS devices, experts discovered portions of the wall concealed by hills, trenches and rivers that stretch from Hu Shan mountain in northern Liaoning province to Jiayu Pass in western Gansu province, the official China Daily reported .

The additional parts mean the Great Wall – construction of which began more than 2,000 years ago to prevent incursions into China by the Mongols and others – spans about 3,900 miles through the northern part of the country.

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