Tunnels are an important part of India's transport infrastructure, particularly in mountainous and strategically sensitive regions. They help overcome geographical barriers, reduce travel time and provide all-weather connectivity to remote areas.
India has constructed several important road, railway and Metro tunnels. Projects such as the Atal Tunnel in Himachal Pradesh, the Sela Tunnel in Arunachal Pradesh and the underwater Metro tunnel in Kolkata have improved connectivity. New projects, including the Zojila Tunnel and Shinkun La Tunnel, are also being developed to strengthen transport and defence infrastructure.
Important Tunnels in India
India has developed an extensive network of road, railway and Metro tunnels to improve connectivity across its diverse geographical regions. The table below highlights some of the major tunnels and their key features.
List of Important Tunnels in India
|
Tunnel |
State/Region |
Important Feature |
|
Atal Tunnel |
Himachal Pradesh |
Bypasses Rohtang Pass and connects Manali with Lahaul Valley |
|
Dr Syama Prasad Mookerjee Tunnel |
Jammu and Kashmir |
Formerly known as Chenani-Nashri Tunnel; located on NH-44 |
|
Banihal-Qazigund Tunnel |
Jammu and Kashmir |
Connects Banihal and Qazigund through the Pir Panjal Range |
|
Sela Tunnel |
Arunachal Pradesh |
Provides all-weather connectivity to Tawang |
|
Sonamarg (Z-Morh) Tunnel |
Jammu and Kashmir |
Improves all-weather connectivity to Sonamarg on the route towards Leh |
|
Tunnel T50 |
Jammu and Kashmir |
Railway tunnel between Khari and Sumber; part of the USBRL project |
|
Kolkata Underwater Metro Tunnel |
West Bengal |
Passes beneath the Hooghly River |
|
Zojila Tunnel |
Jammu and Kashmir-Ladakh |
Under construction; will provide all-weather connectivity to Ladakh |
|
Shinkun La Tunnel |
Himachal Pradesh-Ladakh |
Being developed on the Nimu-Padum-Darcha route |
|
Rishikesh-Karnaprayag Rail Tunnels |
Uttarakhand |
Part of the railway project connecting Rishikesh with Karnaprayag |
|
Mumbai-Ahmedabad High-Speed Rail Tunnel |
Maharashtra |
Includes an undersea section beneath Thane Creek |
Major Operational Tunnels in India
Several major tunnels are now operational across India, particularly in the Himalayan region. They include road and railway tunnels as well as the underwater Metro tunnel in Kolkata.
Atal Tunnel
The Atal Tunnel is a major highway tunnel in Himachal Pradesh that provides all-weather connectivity to the Lahaul-Spiti region.
- It is 9.02 km long and passes through the Pir Panjal Range.
- It connects Manali with Lahaul Valley by bypassing the Rohtang Pass.
- It was inaugurated on 3 October 2020.
- It reduces the road distance by approximately 46 km and travel time by around 4-5 hours.
The Atal Tunnel is recognised as the world's longest highway tunnel above 10,000 feet. Before its construction, the Lahaul-Spiti region often remained cut off from the rest of the country during winter due to heavy snowfall at Rohtang Pass.
Dr Syama Prasad Mookerjee Tunnel
Formerly known as the Chenani-Nashri Tunnel, it is an important road tunnel on National Highway 44 in Jammu and Kashmir.
- It is a 9-km-long, single-tube, two-lane bi-directional tunnel with a parallel escape tunnel.
- It connects the Udhampur and Ramban regions.
- It was inaugurated in April 2017 and renamed in 2019.
- It reduces the road distance by approximately 30 km and travel time by nearly two hours.
The tunnel bypasses difficult and landslide-prone stretches of the Jammu–Srinagar National Highway, making road travel safer and faster.
Banihal-Qazigund Tunnel
The Banihal-Qazigund Road Tunnel, also known as the Navyug Tunnel, improves connectivity between the Jammu region and the Kashmir Valley.
- It is 8.45 km long and has two separate tubes, one for each direction of traffic.
- It passes through the Pir Panjal Range.
- It was inaugurated in April 2022.
- It reduces the road distance between Banihal and Qazigund by approximately 16 km and travel time by around 1.5 hours.
The two tubes are connected through cross-passages at regular intervals, which facilitate emergency evacuation and maintenance. The tunnel provides a more reliable road connection between the two regions, particularly during adverse weather conditions.
Sela Tunnel
The Sela Tunnel is a strategically important road tunnel in Arunachal Pradesh that provides all-weather connectivity to Tawang.
- It is located in the West Kameng district.
- It has been constructed at an altitude of approximately 13,000 feet.
- It is part of the Balipara-Chariduar-Tawang Road.
- It was built by the Border Roads Organisation (BRO) and inaugurated in March 2024.
The project consists of two tunnels, including a twin-tube tunnel with an escape tube. It bypasses the snowbound Sela Pass and improves connectivity along the strategically important Tezpur-Tawang route. It is particularly significant for the movement of defence personnel and supplies towards the India–China border.
Sonamarg (Z-Morh) Tunnel
The Sonamarg Tunnel, popularly known as the Z-Morh Tunnel, improves all-weather connectivity between Srinagar and Sonamarg on the route towards Leh.
- It is located in the Ganderbal district of Jammu and Kashmir.
- The main tunnel is approximately 6.4 km long, with a parallel escape tunnel.
- It is situated at an altitude of around 2,634 metres.
- It was inaugurated in January 2025.
The tunnel bypasses sections of the road that are vulnerable to avalanches and landslides. It has improved access to Sonamarg throughout the year, supporting tourism and connectivity towards Ladakh.
Tunnel T50
Tunnel T50 is an important railway tunnel in Jammu and Kashmir and forms part of the Udhampur-Srinagar-Baramulla Rail Link (USBRL) project.
- It is approximately 12.77 km long.
- It connects Khari and Sumber in Jammu and Kashmir.
- It was inaugurated in 2024.
- It was constructed using the New Austrian Tunnelling Method (NATM).
Tunnel T50 is recognised as India's longest transportation tunnel. It has a main tube and a parallel escape tunnel, connected through cross-passages at intervals of 375 metres. These arrangements help in emergency evacuation and passenger safety.
Kolkata Underwater Metro Tunnel
Kolkata has India's first operational underwater Metro tunnel, which passes beneath the Hooghly River.
- It is approximately 520 metres long.
- It runs around 13 metres below the riverbed.
- It forms part of the East–West Metro Corridor, also known as the Green Line.
- The underwater Metro section became operational in March 2024.
The tunnel connects Howrah and Kolkata beneath the Hooghly River. It is an important example of the use of underground infrastructure to improve urban transport connectivity.
Important Under-Construction Tunnel Projects in India
Several major tunnel projects are being developed in India to improve connectivity in the Himalayan region and strengthen strategic and railway infrastructure.
Zojila Tunnel
The Zojila Tunnel is a strategically important road project being developed to provide all-weather connectivity between the Kashmir Valley and Ladakh.
- It is 13.153 km long and is being constructed between Baltal and Minamarg on National Highway 1.
- It is located at an altitude of approximately 2,900-3,310 metres.
- The project is being implemented by the National Highways and Infrastructure Development Corporation Limited (NHIDCL).
- The main tunnel achieved a breakthrough in June 2026, but the overall project remains under construction.
The tunnel will bypass the Zojila Pass, which frequently becomes inaccessible during winter due to heavy snowfall and avalanches. It is expected to reduce travel time between Sonamarg and Minamarg from around two hours to approximately 30 minutes.
The project is strategically important because it will improve the movement of defence personnel and supplies between Jammu and Kashmir and Ladakh.
Shinkun La Tunnel
The Shinkun La Tunnel is being developed on the Nimu-Padum-Darcha Road to improve all-weather connectivity between Himachal Pradesh and Ladakh.
- It is planned to be approximately 4.1 km long.
- It is located at an altitude of around 15,800 feet.
- It is designed as a twin-tube tunnel.
Once completed, it is expected to become the world's highest tunnel. It will provide an alternative route to Ladakh and improve strategic connectivity to remote border areas.
Rishikesh-Karnaprayag Railway Project
The Rishikesh-Karnaprayag Railway Project is a major railway infrastructure project in Uttarakhand. It aims to improve rail connectivity in the Garhwal region of the Himalayas.
- The railway line is approximately 125 km long.
- It includes 16 main tunnels with a combined length of around 104 km.
- It also includes 12 escape tunnels spanning approximately 98 km.
- The project is being implemented by Rail Vikas Nigam Limited (RVNL).
A large part of the railway line passes through tunnels because of the difficult Himalayan terrain. The project will connect Rishikesh with important towns such as Devprayag, Srinagar and Karnaprayag.
As of October 2026, approximately 79% of the overall project work had been completed. The revised completion target for the entire railway line is December 2029.
Mumbai-Ahmedabad High-Speed Rail Tunnel
The Mumbai-Ahmedabad High-Speed Rail Corridor, also known as the Bullet Train project, includes an underground tunnel section in Maharashtra.
- The underground section is approximately 21 km long.
- Around 7 km will pass beneath Thane Creek.
- The undersea section will be India's first undersea tunnel for a rail corridor.
- The project uses both Tunnel Boring Machines (TBMs) and the New Austrian Tunnelling Method (NATM).
The tunnel will accommodate both railway tracks within a single tube. In July 2026, the second Tunnel Boring Machine began excavation from the Sawli side towards Vikhroli. The project remains under construction.
Challenges in Tunnel Construction in India
Tunnel construction in India, particularly in the Himalayan region, faces several geographical, technical and environmental challenges.
- Complex geology: The Himalayan region has unstable rock formations, fault zones and complex geological conditions.
- Natural hazards: Landslides, earthquakes, avalanches and water seepage increase construction and safety risks.
- High construction costs: Tunnel projects require specialised machinery, skilled workers and advanced safety systems.
- Environmental impact: Construction may affect forests, biodiversity, groundwater and fragile mountain ecosystems.
- Safety and maintenance: Long tunnels require proper ventilation, drainage, fire safety, regular inspection and emergency evacuation arrangements.
Significance of Tunnel Infrastructure for India
Tunnel infrastructure contributes to India's economic development, regional integration and national security.
- Border connectivity: Tunnels such as the Atal, Sela and Zojila projects improve access to strategically important border regions.
- Defence preparedness: All-weather connectivity supports the movement of troops, equipment and essential supplies.
- Tourism: Improved access to destinations such as Lahaul-Spiti and Sonamarg supports year-round tourism.
- Regional integration: Better road and railway connectivity links remote Himalayan settlements with major economic centres.
- Urban mobility: Underground and underwater transport infrastructure helps expand public transportation in densely populated cities.
Last updated on Nov, 2026
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Important Tunnels in India FAQs
Q1. Which is the world's longest highway tunnel above 10,000 feet?+
Q2. Which tunnel connects the Kashmir Valley with the Jammu region through the Pir Panjal Range?+
Q3. Which tunnel provides all-weather connectivity to Tawang in Arunachal Pradesh?+
Q4. Which is India's first operational underwater Metro tunnel?+
Q5. Which railway project includes Tunnel T50, India's longest transportation tunnel?+




