The Great Wall claims to be the only man-made structure on the earth which is visible from the moon. The winding Great Wall can be viewed from the Badaling district, about 75 kilometers to the northwest of Beijing.

It was built during the Warring States period to prevent invasions of nomadic people from the north. The first Qin emperor, who united China into one country, mobilized hundreds of thousands of builders to complete what is known today as the Great Wall of China.

The world-famous Great Wall is 6,700 kilometers long from Shanhaikuan, which overlooks the Gulf of Bo Hai, to Jiayuguan Pass in Gansu province. The wall underwent repeated reconstruction during its 2000-year history, witnessing the historical changes of the Chinese nation.

The Great Wall is magnificent. It is really great that the ancient Chinese constructed such a gigantic structure without any machinery available.