This is the world’s longest wall and the biggest ancient architecture.


Contrary to common belief, the Great Wall of China cannot be seen from space without aid.


As early as the Qin Dynasty (221-207BC) when building the Great Wall, glutinous rice flour was used in making the binding material to bind the bricks.


The labor force to build the Great Wall includes soldiers, forcibly recruited peasants, convicts and war prisoners.


Although the official number of the length of the Great Wall is 8851.8 kilometers (5500 miles), the length of all the Great Wall built over thousands of years is estimated at 21,196.18 kilometers (13,170 miles). The circumference of the Equator is 40,075 kilometers (24,901 miles).


Jiankou section of the Great Wall, known for being steep and winding, enjoys the most frequent appearance on picture books and post cards of the Great Wall.