Combo photo shows the eastern artificial island of the Hong Kong-Zhuhai-Macao Bridge on July 5, 2017 (up) and the western artificial island of the bridge on July 4, 2017 (bottom). The main structure of world's longest cross-sea bridge linking Hong Kong, Zhuhai, and Macao was finished on July 7, 2017. The main structure measures 29.6 kilometers, consisting of a 22.9-km bridge section and 6.7-km underground tunnel. The bridge's total length is 55 kilometers. It has taken seven years to build the bridge, which will be open to traffic at the end of the year. (Xinhua/Liang Xu)