Zoji-la Tunnel

Zoji-La Tunnel, the world's longest single-tube bi-directional road tunnel at the highest altitude, is an under-construction Himalayan tunnel in India under the Zoji La pass between Sonamarg in Ganderbal district of Jammu and Kashmir and Dras in Kargil district of Ladakh. This project is being executed by a Hyderabad-based engineering company, MEIL. It is 9.5 m wide, 7.57 m high and 13.153 km long, horseshoe-shaped single-tube, 2 lane road tunnel at the height of around 11,578 feet above sea level. Together with the adjacent Z-Morh Tunnel, this geostrategically important tunnel on the NH1 Srinagar-Leh Highway will provide year around weather-proof connectivity to Ladakh and Baltal (Amarnath cave), reduce the earlier 1-1.5 hours travel time to just 15 minutes drive, boost the tourism and economy, and enhance the logistics of the Indian Armed Forces. It is one of the 31 road tunnels (20 in J&K and 11 in Ladakh) being constructed at a combined cost of INR1400 billion (~US$17.5 billion).

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