The Northern Mountains

The Northern Mountains These are the Himalayas that stretch across northern India from Jammu and Kashmir to Arunachal Pradesh for about 2,400 km. The Himalayan range has the shape of a crescent. The Himalayas, the worlds's youngest fold mountains, achieve their greatest heights in eastern Nepal.

Breadthwise, the Himalayas may be classified into the following four zones.
(i) The Outer Himalayas or the' Siwaliks With a height ranging from 600 to 1,500m and a width of 15 to 50km, the S'iwaliks are composed of tertiary sediments mainly containing boulder and clay. They emerged in the most recent phase in the Himalayan orogeny, i.e., during the Mi­ocene-Pleistocene epoch.

The Outer Himalayas are separated from the Lesser Himalayas by duns - valleys resulting from draining away of the temporary lakes formed by ridges when these obstructed the course of rivers.

The Lesser or Middle Himalayas (The Himachal) The intricate and rugged hills with deeply-cut rivers are made of rocks of the Algonkian-Eocene times. The Lesser or Middle Himalayan hills have a hogback appearance. The ranges include the 400-km Pir Panjal range, the longest range of the Himalayas.

The Greater Himalayas or the Himadri The innermost Himalayan range is the world's highest, with an average height of 6,000 m. It is the most continuous of the Himalayan ranges and forms the Himalayas' northernmost part. The Himadri's highest peaks include the world's highest peak, Mt Everest.

The Trans-Himalayan Zone With a width of 40 km in its eastern and western ends and a width of 222 km in its central part, it has important ranges such as the Zaskar Range and the Great Karakoram range. The Karakoram extends towards the south-east to form the Kailash Range (Tibet). The highest peak in the Karakoram range is ~ (8,611 m). The longest glacier is Siachen in the Nubra Valley which is more than 72km long.