People dressed up as ancient "terracotta warriors" perform on a street in Shanghai, April 10, 2010. The performance sponsored by the government of Xi'an, capital city of northwest China's Shaanxi Province, is part of the activities to promote the Shanghai Expo. The terracotta warriors and horses were discovered in 1974 in the mausoleum of Qinshihuang, the first emperor of the Qin dynasty who unified China, in northwestern Shaanxi Province. [Xinhua]