Huandao Jiaolong, the world's largest tourism submersible began its trial run in Yalong Bay of Sanya city, South China's Hainan province, on Dec 14, 2015. Developed by a research center under the China Shipbuilding Industry Corporation (CSIC), Huandao Jiaolong was designed for tourism, exploration and adventure travel. Unlike usual submersibles whose cabins are made of metal, Huandao Jiaolong is made of polymethyl methacrylate, and equipped with life-support and navigation control systems.[Photo/IC]