The Atal Tunnel is a road tunnel built under the Pir Panchal Mountains in eastern Himachal Pradesh, India. With a length of 9.02 kilometers, it is the largest tunnel in the world with an altitude of more than 10,000 feet (3048 meters). Single tunnel highway. The tunnel will not only significantly shorten the driving time from Manali to Keylong, but will also change the transportation pattern in the region.
The construction of the Yatal Tunnel has shortened the distance between Manali and Keelung to 71 kilometers and can be reached in about two hours, compared to about three to four hours on the older route.
As early as the 19th century, the Moravian Mission first mentioned the possibility of building a tunnel in the Rohtang Pass. The proposal developed further in the 20th century, with the tunnel's construction first conceived in 1942 by Dr. John Birkennell Oden of the Geological Survey. Then, in 2000, the then Prime Minister Atal Bihari Vajpayee finally took a decision on the construction of the tunnel.
Many challenges were faced during the construction of the tunnel, including heavy winter snow, which made excavation difficult. The north entrance of the tunnel is closed during the winter, making only the south entrance accessible during winter. In addition, there are 46 possible avalanche areas near the tunnel, which is also a major obstacle.
During the entire tunnel construction process, faced with a large number of rock and soil processing problems, as well as the entry of up to 300,000 liters of water per day, the construction speed once dropped to only 0.5 meters per day.
The Atal Tunnel was built using New Austrian Tunneling Technology (NATM) and was designed with harsh climatic conditions in mind. The total length of the tunnel is 9.02 kilometers, but its height is 3,100 meters (10,171 feet), which is 3,978 meters (13,051 feet) higher than the Rota Pass, giving drivers and passengers a safer driving environment.
An indirect ventilation system is used inside the tunnel and emergency evacuation passages are provided to ensure quick and safe evacuation in case of emergency.
The completion of the tunnel will not only change the way people travel, but will also greatly promote tourism in Himachal Pradesh. With better access, more tourists will be able to explore this beautiful, underexplored area, which will bring new economic vitality to the area.
The successful construction of the Yatar Tunnel not only demonstrates a breakthrough in engineering technology, but also symbolizes the indomitable spirit of mankind in the face of natural challenges. Faced with such a spectacular project, we can think about: In the future, what kind of construction achievements will surprise us?