Sela Tunnel

Sela Tunnel is an existing operational road tunnel on NH-13 at 3,000 metres (9, 800 ft) which ensures all-weather connectivity between Guwahati in Assam and Tawang in Arunachal Pradesh. This tunnel is the longest bi-lane tunnel in the world at 13,000 feet. Situated 400 metres below the Sela Pass, the Sela Tunnel offers a vital passage, especially during the winter season. The tunnel helps move troops, weapons, and machinery quickly along the Sino-India border. It is connected with NH13 by a new 12.4 km road and has reduced the distance between Dirang and Tawang by 10 km. Executed by the Border Road Organisation (BRO), the project features two tunnels and a link road. Tunnel 1 is a 980-metre-long single-tube tunnel, while Tunnel 2 is a 1,555-metre-long twin-tube tunnel, with one bi-lane tube for traffic and the other for emergency services. The link road between these tunnels spans 1,200 metres. The tunnel provides access to Tawang by an all-weather road in the western region of Arunachal Pradesh throughout the year.

Tunnel data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).