This photo taken on July 30, 2026 shows an exterior view of the launch shaft for the shield tunneling machine "Linghang" of the Chongming-Taicang Yangtze River tunnel in Chongming District, east China's Shanghai. China's domestically developed, world's largest-diameter high-speed-rail shield tunneling machine "Linghang" completed tunneling of the underwater section of the Chongming-Taicang Yangtze River tunnel on Thursday. The milestone lays the foundation for China's first high-speed railway crossing beneath the Yangtze River at 350 kilometers per hour without slowing down. (Xinhua/Fang Zhe)