Photo taken on Oct. 24, 2018 shows vehicles running on the Hong Kong-Zhuhai-Macao Bridge. After nine years of construction, the world's longest bridge, the Hong Kong-Zhuhai-Macao Bridge, has opened to traffic, giving a strong boost to the development of the Guangdong-Hong Kong-Macao Greater Bay Area. The 55-km bridge, situated in the waters of Lingdingyang of Pearl River Estuary, connects the Hong Kong Special Administrative Region (SAR), Zhuhai and the Macao SAR. The bridge is the first of its kind for Guangdong, Hong Kong, and Macao to jointly build a supergiant sea-crossing traffic project under the principle of "one country, two systems." (Xinhua/Wu Xiaochu)