Carved onto every weld joint of the "Bird's Nest" are the names of the welders who were in charge of it.

In order to ensure the success of construction, about 450 welders were chosen out of more than 1,000 of China's top welders. They went through tough training and finally earned a pass into the construction site of the National Stadium.

The welding work of the "Bird's Nest" is complicated. Sometimes, welders had to work in a narrow space for quite a long time.

Most of the welding was done in the summer, when the weather was hot. In order to achieve the best quality, each steel plate had to be heated up to 150 degrees Celsius, and all welders needed to put on heavy clothes to keep them from burning.

Once welding work is started, breaks are not allowed. Otherwise, problems would occur. The longest welding project lasted 17 hours. Although workers could be changed, it was still a challenge, both physically and mentally.

During the peak of the welding work, there were thousands of welders working at the construction site. Moreover, there were 7,000 cement workers. The "Bird's Nest" was built by them.

Each weld joint on the "Bird's Nest" was carved with the names of the welders who were in charge of it. There is no chance for spectators to see them, but in this way, thousands of welders wrote their names in history.

Narrator: Li Jiulin, Chief engineer of the Beijing Urban Construction National Stadium General Contracting Department