A visitor experiences a virtual cockpit of Chinese high-speed train in Ankara, Turkey, on May 8, 2018. The 10th World Congress on High-Speed Rail and Trade Exhibition was held in Ankara from May 8 to 11 with over 1,000 high-speed rail experts from all around the world meeting in the event themed "sharing knowledge for sustainable and competitive operations."(Xinhua/Qin Yanyang)