High Quality Content by WIKIPEDIA articles! Rohtang Tunnel is a tunnel being built under the Rohtang Pass in the eastern Pir Panjal range of the Himalayas on the Leh-Manali Highway. With 8.8 km (5.5 mi) length, the tunnel will be one of the longest road tunnel in India (the longest road tunnel in India will be the Chenani-Nashri Tunnel or Patnitop tunnel north of Udhampur) and is expected to reduce the distance between Manali and Keylong by about 60 km (37.3 mi) The tunnel is at 3,100 metres (10,171 ft) elevation whereas the Rohtang pass is at 3,978 metres (13,051 ft) elevation 51 km (32 mi) away from Manali. The pass receives heavy snowfall and blizzards during winter months for about four months and is open for road traffic for only four months in a year. Lying on the Manali-Leh axis, this is one of the two routes to Ladakh. The other route through the Zoji La pass on the Srinagar-Drass-Kargil-Leh highway also gets blocked by snow for nearly four months in a year. These two routes are vital to feed military supplies into the sub-sector west (facing Aksai Chin) and the Siachen Glacier.