The Great Wall of China is a Chinese fortification built from 3rd century BC until the beginning of the 17th century, in order to protect the various dynasties from raids by Mongol, Turkic, and other nomadic tribes coming from areas in modern-day Mongolia and Manchuria. It was to protect China from the invasion of the Xiongnu people from Mongolia. The Xiongnu tribe was China's main enemy at that time and therefore the chinese built the Great Wall to prevent them from entering and conquering China and also to attack and repel to Xiongnu people by shooting arrows and firing cannonballs at them from the Great Wall, which was cleverly designed with small holes in the walls for defense and attack at the same time. Although the building of the architectural wonder sacrificed many lives, it was still worth it in the end as the Mongolians might have killed many more chinese while inside China, and it contributed in tourism in the later years too, although that was not the main reason for building it.
