Xi'an is another of China's most ancient site. It has been inhabited for about 6000 years.
In the early 6th century Xi'an had two million inhabitants and was enclosed by a city wall that was roughly 5 miles by 8 miles.
The city is home to one of China's largest mosques.
Xi'an's Big Goose Pagoda in the city was built to house Buddhist manuscript brought from India by a monk in 652 AD. The monk, named Xuan Zhang, translated the Buddhist manuscripts into 1335 volumes of Chinese text.
But Xi'an is perhaps most famous for the Terracotta Warriors discovered there in 1974. It is one of the world's great archaeological sites. Some 8000 terracotta warriors guard the body of a Chinese Emperor.