Indian Railways is planning a massive infrastructure project to secure the Siliguri Corridor, often called the Chicken’s Neck. The government will construct a blast-proof and disaster-resistant underground double railway line to ensure that the Northeast remains connected to the rest of the country even during emergencies. This strategic move aims to reduce vulnerability in a region close to international borders.
What are the key details of the underground project?
The project involves building an underground rail network of about 170 kilometers. The tracks will be laid 20 to 24 meters below the surface using Tunnel Boring Machines (TBM) to protect them from surface-level threats. This network will pass through Bihar and West Bengal, with the most sensitive section being a 34-40 km stretch between Tin Mile Hat and Rangapani in West Bengal.
| Feature | Details |
|---|---|
| Estimated Cost | ₹51,000 Crore |
| Total Underground Length | 170 Kilometers |
| Target Completion Year | 2033 |
| Depth of Tracks | 20-24 Meters |
| Key States | West Bengal and Bihar |
| Total Lines in Corridor | 6 (4 Overground + 2 Underground) |
How will this impact connectivity and security?
The existing double-track line will be upgraded to a four-line overground section, meaning there will be a total of six lines in the corridor. This setup provides flexibility and higher capacity for troop and cargo movement. According to NFR officials, one of the underground lines will connect toward Bagdogra, which is vital for India’s air defense. Additionally, these tunnels are designed to support future Bullet Train operations, specifically for the proposed Varanasi-Siliguri-Guwahati high-speed corridor.
What are the latest official updates?
Rail Minister Ashwini Vaishnaw announced the strategic plans in February 2026, and the Union Cabinet gave its formal approval on February 15, 2026. To further strengthen the region, the Railway Board approved 14 Final Location Surveys (FLS) on July 3, 2026, to improve connectivity with Nepal and Bangladesh. The government also allocated ₹11,486 crore in the 2026-27 budget for various railway projects across Assam and the Northeast.
Frequently Asked Questions (FAQs)
What is the total length and cost of the underground railway project?
The total underground length will be approximately 170 kilometers, and the estimated cost of the project is around ₹51,000 crore.
When is the project expected to be completed?
The Indian government has set a target to complete this strategic underground railway project by the year 2033.