During the height of the Tang dynasty (7th–10th century C.E.) Chang'an (later Xi'an), the eastern terminus of the Silk Road, was considered to be the most cultured and cosmopolitan city in the world. At the center of the imperial city stood the great Bell Tower, which marked time and resounded for celebrations and in times of calamity.
The founder of the Han dynasty built a new capital city in 194 B.C.E. and named it Chang'an (Eternal Peace). During the Han dynasty (206 B.C.E.–220 C.E.) silk was first sent across the Silk Road to Rome and the court of Emperor Augustus. The Han, forced by invaders to move east, abandoned Chang'an in 25 C.E. It was not until the Tang dynasty that Chang'an was rebuilt as a capital city.
Meticulously planned, Chang'an, as is typical of most Chinese cities, was laid out like a chessboard and aligned on the cardinal points of the compass. The city was purposely built to be the capital of a great empire. It was considered so grand and so well laid out that the Japanese modeled their two imperial capitals, Nara and Kyoto, on Chang'an. Many of the objects housed in the Shosoin repository in Todaiji Temple in Nara come from Tang China. The Silk Road flourished during the Tang with trade in jade, porcelain, silk, oranges, peaches, pears, cast iron, gunpowder, crossbows, paper, and printing. The trade along the Silk Road also encouraged an exchange of art and religion, and Chang'an during the Tang was a religious center. During its early years, Tang China was tolerant of all religions, and Muslims, Nestorian Christians, Zoroastrians, and Buddhists practiced their faith there. The city was also home to many foreign students; for instance, in 640 there were said to be 8,000 Korean students in Chang'an.
Today Xi'an is the capital of Shaanxi Province. People from all over the world visit to see the famous terra cotta warriors guarding the tomb of Qin Shihuangdi, the emperor who in the 3rd century B.C.E. unified the many contending states in central China to establish the Qin dynasty. His capital was near present-day Xi'an.