Xi'an's city history dates back to more than 3,000 years. It served intermittently as the capital of eleven dynasties for 1,100 years. As the starting point of the famous "Silk Road," Xi'an became (from the Han Dynasty) the hub of economic and cultural exchange between China and the out-side world. Today, many people know Xi'an, also because of the Terra Cotta Warriors buried in Qin Shi Huang's tomb in 210 BC (following his command, The Great Wall of China was built 2000 years ago).