That title belongs to the Laerdal Tunnel in Norway. the longest road tunnel in the world. That title belongs to the Lerdal Tunnel in Norway. But hold on to your hard hats, because China has its sights set on shattering records. They're planning an astonishing 105.25-kilometer railway tunnel between Yantai and Dalian that will make other tunnels look like mere molehills. This is all part of China's quiet revolution in high-speed rail.