The National Stadium, as the main track and field stadium for the 2008 Olympics Games, is dubbed the 'bird's nest' because of its innovative grid formation.The stadium was begun in March 2004 and finished in March 2008. It was built with 36 kilometers of unwrapped steel, with a combined weight of 45,000 tonnes. Covering over 258,000 square meters, the stadium has at least 100,000 seats. [manqingwangye/jingnei.net]