the world's longest tunnel

China wants to build a 1,000km tunnel to lead water from Tibet to Xinjiang
The South China Morning Post quoted project-related experts as saying the plan would
The world's longest tunnel is officially completed in Switzerland
The longest tunnel in the world with a length of more than 56km through the Alps has been completed in Switzerland.
China built the world's longest sea tunnel
The tunnel construction project under Bohai Bay connecting Dalian port city in Liaoning province and Yantai city in Shandong province was launched in 1994.