On that day, at the Haimen of Nantong, Jiangsu, where the Yangtze River flows into the sea, China's independently developed "Jianghai" shield machine with a maximum excavation diameter of 16.64 meters slowly started, and the new "First Tunnel of the Yangtze River" and the longest underwater shield tunnel for highways in China, the Haitai Yangtze River Tunnel, was officially excavated. The Haitai Yangtze River Tunnel starts from Haimen District in Nantong in the north and ends at Taicang City in Suzhou in the south. The total length of the route is 39.07 kilometers, including 11.185 kilometers of cross river tunnels. It adopts the design standard of a two-way six lane expressway and is designed for a speed of 100 kilometers per hour. The shield tunnel section constructed by China Railway 14th Bureau is 9315 meters long. The interior of the "Jianghai" shield tunneling machine captured on April 9th. On April 9th, staff from China Railway 14th Bureau carried out pipe segment assembly operations inside the "Jianghai" shield machine. On April 9th, technicians from China Railway 14th Bureau were working in the shield machine operating room. On April 9th, technicians from China Railway 14th Bureau were working in the shield machine operating room. On April 9th, technicians from China Railway 14th Bureau conducted an inspection inside the "Jianghai" shield tunneling machine to ensure its normal operation. On April 9th, technicians from China Railway 14th Bureau conducted an inspection inside the "Jianghai" shield tunneling machine to ensure its normal operation.