The Great Wall of China was constructed over many centuries, with the earliest sections built as early as the 7th century BC. The main purpose of the wall was to defend against invading Mongol tribes. Over time, the wall was continually expanded and rebuilt by various dynasties, reaching its maximum size during the Ming Dynasty (1368-1644). The Great Wall is estimated to be over 13,000 miles long and was built using materials such as brick, tamped earth, stone, and ceramic. Despite being a massive engineering feat, the Great Wall did not serve its intended purpose of keeping invaders out, as it was eventually breached. However, it remains an iconic symbol of China's rich cultural and military history. The Great Wall of China was built by a combination of soldiers, peasants, and prisoners over many centuries. During times of peace, soldiers were often used to build and maintain the wall. During times of war, conscripted peasants and prisoners were also used to build the wall. The constr