What is the longest tunnel in the world?

The longest tunnel in the world is the Saint Gotha Baseline Tunnel.

Located in the south of Switzerland, the Saint-Gotha Baseline Tunnel is also the longest tunnel in the world (including railway tunnel and highway tunnel). Across the Alps. The main tunnel is two parallel single-line tunnels with a length of more than 57 kilometers. The total length of the East and West tunnels, together with other auxiliary shafts and communication passages, is151.8km.. Due to the huge project, the whole tunnel took 17 years to complete.

It is also the deepest railway tunnel in the world, with a depth of 2300 meters. On June, 2065438, the entire tunnel was officially opened, and on June, 2065438+February, 2065438, the tunnel was officially put into normal operation.

The longest tunnel in China.

Zhong Nanshan Highway Tunnel in Qinling Mountains has a single tunnel length of 18020m and a total length of 36040m. It started in March 2002 and was completed and opened to traffic in June 5438+ 10, 2007, which was the largest construction scale at that time. China Highway Tunnel was the longest double-tunnel expressway tunnel in the world at that time. This is a super-long highway tunnel with independent intellectual property rights independently designed by China, which is of milestone significance. Tunnel design concept: people-oriented, serving traffic, advanced technology, safety and reliability, economy and practicality, environmental protection and beauty, one-time design and phased implementation.

The pavement in the tunnel is cement concrete pavement, and the lining design is composite lining. According to the tunnel length and traffic volume, the tunnel traffic engineering level is Grade I. Facilities such as ventilation system, monitoring system, disaster prevention and rescue system, lighting system, power supply and distribution system, communication system, traffic engineering, monitoring center, fire control duty room, dangerous goods inspection station, south exit rest area and special lighting belt are provided. Operation ventilation adopts three-axis sectional longitudinal ventilation mode.