The National Stadium (Bird's Nest), the main stadium of the 29th Summer Olympic Games, locates at the central area of Beijing Olympic Park and covers an area of 20.4 hectares with construction area of 258 thousand m2, which can accommodate 91,000 audiences. It is a superfine sports building with 100 years of designed service life for its main structure, and its main building has ellipse nest shape which is weaved by a series of steel truss around the bowl-shaped seating area with 333 meters long from north to south, 296 meters wide from east to west, and 69 meters high at the highest point. The construction of the National Stadium started on December 24, 2003 and ended on June 28, 2008.
The National Stadium stands on the base platform with a slope slowly up from the ground. The audience can reach the stadium from the Olympic Park along the base platform. At the north side of the base, it is a sunken warm-up venue, connecting the playing field of main venue through athlete channel. The stadium consists of seven layers above the base including audience service facilities, media area, VIP reception area and commercial area etc, and three layers below the base including a zero-layer inner loop, parking lot and a large number of functional rooms. The bowl-shaped grandstand (bleachers) consists of three layers - upper, middle and lower layers with boxes and seating area between the upper and middle grandstands.
The advanced energy-saving design and environmental protection measures were adopted in the construction of the National Stadium, such as good natural ventilation and natural lighting, overall recovery of rainwater, renewable geothermal energy utilization, and application of solar photovoltaic power generation technology etc, which is a truly large-scale "green building".