The National Stadium, also known as the Bird's Nest, is now complete after more than four years' work. The stadium is one of the world's most complicated steel-made constructions.

Working staff and guests pose for photos in front of China's National Stadium, known as the Bird's Nest, in Beijing, capital of China, June 28, 2008. It was announced early Saturday that China's National Stadium is fully operational, singaling the readiness of all 37 venues for the upcoming Beijing Olympics in August. (Xinhua/Luo Xiaoguang)

The Bird's Nest is the main stadium for the Beijing Olympics. It has a capacity for almost one hundred-thousand spectators.

The huge construction required extremely stringent requirements for steel quality. Chinese researchers invented a special kind of steel to satisfy the standard. More than 110-thousand tons of steel were used.

Tan Xiaochun, Beijing Urban Construction Group, said, "The weld seam on the Bird's Nest has a length of 320 kilometers. More than a thousand welders worked on the project for fifteen months. It's a miracle in China's construction history."

Nearly nine hundred pieces of protective overhang were installed on the stadium's roof. They protect the lighting inside the

Bird's Nest and also protect the spectators from rain.

Li Aiqing, Board Chairman of National Stadium, said, "There are three layers of stands in the stadium. We can evacuate all the audience to safe places in eight minutes."

On August the eighth, the Beijing Olympics will officially begin at the Bird's Nest. The stadium will play host to China's first ever Olympics.

(CCTV July 1, 2008)