The great wall of China is a series of fortifications made of stone and soil in North China, which was built to protect the northern borders of the Chinese Empire from invasion of nomadic peoples. The great wall stretches from Shanhaiguan in the East to Lop Lake to the West. This wall has a long 8.851 .8 km (5,500.3 mi), consisting of 6.259 .6 miles (3.889, 5 miles) of the wall that is truly, 359,7 km (223, 5 miles) moat and 2.232 .5 miles (1,387, 2 mile) natural fortifications such as hills and rivers. These walls have been built since the 5th century BC, known as the great wall but the most famous is the wall built in 220-206 BC we know today.