A Defensive Failure

The wall's record as a military barrier is embarrassingly poor:

• Genghis Khan's Mongols simply rode around it or bribed guards to open the gates in the early 1200s
• The Manchu invasion of 1644 succeeded when a Ming general opened the gates at Shanhai Pass to let them through
• Nomadic raiders regularly crossed using unguarded sections in remote mountains

The wall was never meant to stop a determined army. It was built to slow small raiding parties and control the movement of people and goods. As a customs checkpoint it worked reasonably well; as a fortress it was a spectacular failure. Its greatest legacy may be cultural rather than military.