Xi'an, the capital of Shaanxi Province, was called Chang'an in ancient times. It is situated in the central part of Weihe Plain. The city is bounded by the Weihe River in the north and the Qinling Ranges in the south. As one of China's seven ancient national capitals, it served as the capital for 12 dynasties spanning more than 1,000 years. Xi'an therefore, has a great number of precious relics and historical sites. More than 4,000 historical sites and tombs have been excavated and over 120,000 historical relics remain unearthed.