"We opted to use translucent materials to fill the spaces between grid-like steel structures as we intend to attract spectators' attention to athletes' performance, and the bowl-shaped stands we designed can bring together all spectators who encompass the athletes or artists," said Li Xinggang, deputy chief architect of the China Architecture Design and Research Group.

"Those who are competing for s sport title at the venue or giving an art performance on the stage will be more enthusiastic when seeing such amused crowds," he added.

"Contrary to what many image, we put the design of the project's inner part first, focusing on spectators' stands, the core part of a sport facility. They are classically stayed, looking ancient Roman or Greek," Li said. The east and west sides of the stands are designed to be higher than south and north sides, in favor of spectators' sightlines.

The National Stadium will be used for opening and closing ceremonies, track and field events, and football finals during the Olympics and after 2008, it will be used for large-scale sport competitions, conventional competitions as well as business and cultural activities.

Despite zigzags in the design process, the principal concepts remained unchanged, according to Li. "We optimized the design by omitting the originally designed retraceable roof and enlarging the size of the rooftop opening, resulting in less steel use, but the bird's nest is still the bird's nest."