A pioneering infrastructure project is taking shape in Uttar Pradesh, as construction progresses on an underground highway tunnel beneath the active runway of Lal Bahadur Shastri International Airport in Varanasi. Once completed, the project will mark the first time in India that a national highway operates directly below a functioning airport runway.
The tunnel is a critical component of a broader 2.89-kilometre realignment of National Highway 31, designed to resolve long-standing traffic constraints around the airport while unlocking major expansion potential for aviation infrastructure. Within the airport boundary, the underground section will stretch close to 450 metres, allowing continuous road movement below ground as aircraft operations continue uninterrupted above.
Work on the project commenced in September 2025 and is being implemented at an estimated investment of around Rs 250 crore. Engineers have designed the tunnel with exceptionally high safety benchmarks, accounting for the complex demands of supporting an operational runway overhead. The structure is built to endure extreme stress scenarios, including blast loads equivalent to 100 tonnes of TNT, reflecting the strategic importance and sensitive nature of the site.
With the tunnel in place, surface traffic near the runway area will be completely eliminated, significantly enhancing airside safety while improving traffic efficiency for road users. Although road corridors intersect taxiways at some Indian airports, the Varanasi project stands apart as the country’s first example of a national highway passing directly beneath an active runway.
The tunnel is expected to be completed by the third quarter of 2027. Following its commissioning, the Airports Authority of India plans to undertake a major runway extension, increasing its length from 2,745 metres to 4,075 metres. This upgrade will enable the airport to accommodate Code E wide-body aircraft, including models such as the Boeing 777, supporting future growth in long-haul connectivity and passenger capacity.
