The National Stadium (Bird's Nest) is located in the south of the central area of Beijing Olympic Park, which is the main stadium of the 2008 Beijing Olympic Games. The project covers a total area of 21 hectares, with about 91,000 audience seats. The Olympic Games were held, the opening and closing ceremonies of the Paralympic Games, the final competitions of track and field matches and football matches were held. After the Olympic Games, it has become a large professional place for Beijing citizens to participate in sports activities and enjoy sports entertainment, as well as a landmark sports building and Olympic heritage. The stadium is designed by Jacques & Herzog, Demeron, Ai Weiwei and Li Xinggang, and constructed by Beijing Urban Construction Group. The shape of the stadium is like the "nest" and cradle that breeds life, and it is the hope of human beings for the future. Designers did not do any superfluous treatment to the venue, exposed the structure, and thus naturally formed the appearance of the building. Construction started on December 24, 2003 and completed in March 2008 with a total cost of 2.267 billion yuan. As a national landmark building, the main stadium of the 2008 Olympic Games, the structure characteristics of the National Stadium are very remarkable. The stadium is a super sports building and a large stadium. The main structure design has a service life of 100 years, the fire-resistant grade is one, the seismic fortification intensity is eight, and the underground waterproof grade is one. In April 2014, China's top ten contemporary building evaluation committees initially evaluated 20 buildings from more than 1,000 landmark buildings in China, including four indicators: age, scale, artistry and influence. Eventually, ten contemporary buildings emerged. Beijing Bird's Nest, the National Stadium, is one of the first selected buildings.