Cargo vessels wait to pass the ship lock at the Three Gorges Dam, a gigantic hydropower project on the Yangtze River, in Zigui County of Yichang City, central China's Hubei Province, Jan. 7, 2018. The throughput at the ship locks of the Three Gorges hydropower project reached a record high of 138 million tonnes in 2017. The Three Gorges project is a multi-functional water control system, consisting of a 2,309-meter-long and 185-meter-high dam, a five-tier ship lock and 26 hydropower turbo-generators. The project generates electricity, controls flooding by storing excess water and helps to regulate the river's shipping capacity. (Xinhua/Zheng Jiayu)