The main torch was checked and approved at its construction location. [Luo Chonggeng/Shougang Daily]

The slide shows the main torch tower in place on the top of the Bird's Nest at the press conference on August 12, 2008. [Wang Wei/China.org.cn]

The TS project was more than a process of research and design, Zhu said. From blueprint to the installation of the main tower itself on the top of the Bird's Nest, the project team faced a series of challenges. In addition to assembling the main torch tower, they had to ensure its steady elevation to the top of the stadium and a smooth mounting on the supporting tracks into its exact position for the successful lighting.

The main torch tower rested on its side on the top of the Bird's Nest before being raised up on the evening of August 8. In order to ensure the secrecy of the whole project, it was concealed by an apparatus measuring 100m x 50m.