Regional divisions of the Himalayas and the cold desert of Ladakh

Detail

1. Why divide the Himalayas into regions?

• The Himalayas run west to east as one long chain of mountains. Relief, climate, people and land use change along this chain, so geographers split it into regional divisions.
• The current NCERT Class 11 chapter does not list these divisions. They come from the earlier edition of the same chapter and are still asked in exams.
• The five divisions, from west to east: 1. Kashmir or North-western Himalaya 2. Himachal and Uttarakhand Himalaya 3. Darjeeling and Sikkim Himalaya 4. Arunachal Himalaya 5. Eastern Hills and Mountains (Purvachal)

Division	Extent / boundary	Key relief	Key people, land use and features
Kashmir / North-western	Westernmost part	Karakoram, Ladakh, Zaskar, Pir Panjal ranges	Kashmir valley, karewas (saffron), Dal and Wular lakes, cold desert
Himachal and Uttarakhand	Between the Ravi (west) and the Kali (east) rivers	Western Himalayan ranges and valleys	Valley of Flowers, Bhotia transhumance to bugyals, Great Himalayan National Park
Darjeeling and Sikkim	Between Nepal (west) and Bhutan (east)	Kanchenjunga	Tea gardens, Duars, Lepcha people
Arunachal	From east of Bhutan to the Diphu pass (east)	Kangto, Namcha Barwa	Monpa, Abor, Mishmi, Nishi, Naga; jhum cultivation
Purvachal	Along the Myanmar border, running north to south	Patkai Bum, Naga, Manipur, Mizo hills; Barail range	Loktak lake; "Molassis basin" in Mizoram

2. Kashmir or North-western Himalaya

• Ranges: the Karakoram, Ladakh, Zaskar and Pir Panjal.
• Kashmir valley: a wide valley between the Greater Himalaya and the Pir Panjal.
• Lakes: Dal and Wular, both in the Kashmir valley.
• Karewas: thick beds of clay and other deposits. They were laid down in old lakes fed by glaciers. When the lakes drained, these flat clay beds were left behind.

• Use: karewas are the main land for growing saffron (zafran).

• Cold desert: the land between the Greater Himalaya and the Karakoram is a high, dry, cold desert (see Section 7).

3. Himachal and Uttarakhand Himalaya

• Extent: between the Ravi in the west and the Kali in the east. The Kali also marks the India–Nepal border.
• Valley of Flowers: a high meadow full of alpine flowers in Uttarakhand.
• Bhotia herders and bugyals:
• Transhumance means herders move with their animals between seasons. They go up to high pastures in summer and come down to the valleys in winter.
• The Bhotias take their herds to summer grasslands called bugyals.

• They come back down when snow covers the high land in winter.

• Great Himalayan National Park (GHNP): a protected area in Himachal Pradesh.

• Listed as a UNESCO World Heritage Site in 2014 as the "Great Himalayan National Park Conservation Area". It was listed under criterion (x), which is for important natural homes of rare and threatened plants and animals [2][3].
• Area and height: 90,540 ha. Heights run from peaks above 6,000 m down to river-side forest below 2,000 m [2].
• Rivers: it holds the upper glacier and snow-melt sources of the Jiwa Nal, Sainj, Tirthan and Parvati rivers [2].
• Wildlife: the Himalayan monal (a pheasant) and the snow leopard. Records include 805 vascular plant species, 31 mammal and 209 bird species. About 58% of its flowering plants are found only in the Western Himalaya (UNESCO evaluation, 2014) [2].

4. Darjeeling and Sikkim Himalaya

• Extent: between the Nepal Himalaya in the west and the Bhutan Himalaya in the east.
• Peak: Kanchenjunga, India's highest peak, on the Sikkim–Nepal border.
• Tea gardens: tea is grown on the hill slopes around Darjeeling.
• Duars: the foothill plains below the Bhutan and Darjeeling hills. Tea gardens were also set up here.
• People: the Lepcha, the native tribe of Sikkim and Darjeeling.

5. Arunachal Himalaya

• Extent: from the east of Bhutan to the Diphu pass in the east, near where India, China and Myanmar meet.
• Peaks: Kangto and Namcha Barwa. The Brahmaputra (called the Tsangpo in Tibet) bends round Namcha Barwa and enters India through a deep gorge.
• People (west to east): the Monpa, Abor, Mishmi, Nishi and Naga.
• Jhum cultivation: a type of shifting cultivation.
• Farmers cut and burn a patch of forest and grow crops on it for a few years.
• When the soil loses its fertility, they move to a new patch.

• The old patch is left so that the forest can grow back.

• Valleys (west to east): Kameng, Subansiri, Dihang (Siang), Dibang and Lohit. All of these rivers flow into the Brahmaputra system.

6. Purvachal (Eastern Hills) and the north-western wall

• Purvachal: the eastern hills, where the Himalayan system bends south along the India–Myanmar border.
• Rocks: mostly sedimentary rocks, which form from layers of sand and mud.
• Hills (north to south): Patkai Bum → Naga hills → Manipur hills → Mizo (Lushai) hills.

• Barail range: lies between these hills and separates the Naga hills from the Manipur hills.

• Loktak lake (Manipur): the largest natural freshwater lake in north-east India. It is a Ramsar site [6].

• Phumdis: floating mats of soil and plants on the lake [5][6].
• Keibul Lamjao National Park: the world's only floating national park, built on the largest phumdis. It is home to the Sangai (Manipur brow-antlered deer) [5].

• Size: the lake is oval, about 26 km long and 13 km wide, with an average depth of 2.7 m [5].

• Molassis basin (Mizoram): a basin made of soft, unconsolidated deposits. These are loose layers that have not yet hardened into rock.

• North-western wall: the Hindukush (Afghanistan) and the Sulaiman ranges (Pakistan) close off the subcontinent in the north-west.
• The Khurram, Tochi and Gomal rise in the Sulaiman ranges.
• They join the Indus from its right (west) bank.

7. The cold desert

• Cold desert: a region that is dry, high and freezing. Little rain falls, and winters are bitterly cold.
• Where: Ladakh and Lahaul-Spiti (Himachal Pradesh). Ladakh is now a Union Territory [8].
• Why it is dry: the rain shadow.
• The monsoon winds blow in from the south and hit the Greater Himalaya.
• These winds rise, cool and drop their rain on the southern side.

• The air that crosses over to Ladakh is dry. This sheltered dry side is the rain shadow.

• Climate:

• Rain: less than about 10 cm a year (NCERT: Class 11, Climate).

• Cold: winter temperatures fall below −30°C. Drass reaches about −45°C.

• Ranges: the Karakoram, Ladakh and Zaskar ranges.

• Cold Desert Biosphere Reserve (Lahaul-Spiti):
• Added to UNESCO's World Network of Biosphere Reserves on 27 September 2025. It became India's 13th UNESCO biosphere reserve [4][7].
• Height: 3,300–6,600 m [4].
• Parts: Pin Valley National Park, and the Kibber and Chandratal Wildlife Sanctuaries [4].
• Wildlife: snow leopard, Himalayan ibex, blue sheep and Himalayan wolf [4].
• People: they keep yaks and goats and grow barley and peas [4].

8. Life in Ladakh

• Land:
• The landscape is called a "moonland": bare land of eroded sand and clay.

• These sediments were once laid down on an ocean floor (the old Tethys Sea). They were lifted up when the Himalayas formed.

• Salt lakes:

• Pangong Tso is a salty lake.
• Tsomoriri (Ramsar site) lies at 4,595 m. It has no outflow, so water is lost only by evaporation. This makes its water fresh to brackish (slightly salty) [9].

• Tso Kar Wetland Complex (above 4,500 m, Changthang) became India's 42nd Ramsar site in December 2020. It was the second Ramsar site in Ladakh. It has the freshwater Startsapuk Tso and the very salty (hypersaline) Tso Kar [8][10].

• Animals: snow leopard, ibex and Tibetan antelope.

• Yaks give milk, wool and dung, which is used as fuel, and they carry loads.

• Culture: Buddhist monasteries, and the Losar (new year) and Hemis festivals.

Prelims Hooks

• West to east order: Kashmir → Himachal–Uttarakhand → Darjeeling–Sikkim → Arunachal → Purvachal.
• The Himachal–Uttarakhand Himalaya lies between the Ravi and the Kali rivers. The Arunachal Himalaya runs from Bhutan to the Diphu pass.
• Karewas are glacial-lake clay beds in the Kashmir valley and are used for saffron. Bugyals are summer pastures in Uttarakhand used by the Bhotias.
• Great Himalayan National Park (Himachal Pradesh): a UNESCO natural World Heritage Site in 2014, under criterion (x) [2][3].
• Purvachal hills, north to south: Patkai Bum → Naga → Manipur → Mizo (Lushai). The Barail range lies in between.
• Arunachal valleys, west to east: Kameng → Subansiri → Dihang → Dibang → Lohit.
• Khurram, Tochi and Gomal are right-bank tributaries of the Indus that rise in the Sulaiman ranges.
• Cold Desert Biosphere Reserve: in Lahaul-Spiti. In 2025 it became India's 13th UNESCO biosphere reserve [4][7].
• Loktak: the largest freshwater lake in north-east India. It has phumdis and the Sangai in Keibul Lamjao [5][6].
• Ladakh lakes: Tso Kar became India's 42nd Ramsar site in 2020 [8]. Tsomoriri is a Ramsar site at 4,595 m [9]. Pangong Tso is salty.

Mains Points

• Relief shapes ways of living (GS-I):
• Kashmir uses karewas to grow saffron.
• Uttarakhand herders practise transhumance to bugyals.
• Darjeeling and the Duars grow tea.
• Arunachal farmers practise jhum.
• Ladakh herders depend on yaks.

• Each region uses its land in its own way.

• Rain shadow and the cold desert:

• The Greater Himalaya stops the monsoon winds.
• So Ladakh and Lahaul-Spiti get under about 10 cm of rain and face winters below −30°C.

• People here live by herding and growing barley in small oases fed by glacier water. Shortage of water is the main problem of the region.

• Protected areas in fragile mountains (GS-III):

• GHNP (UNESCO, 2014) protects river sources and western Himalayan species [2].
• The Cold Desert Biosphere Reserve (UNESCO, 2025) and the Ramsar wetlands of Ladakh protect high, dry ecosystems [4][8][9].

• Loktak's phumdis and the Sangai show that wetlands in the north-east also need protection [5][6].

• Purvachal hills: they are made of soft sedimentary rock and have heavy rain. Jhum cultivation adds to soil erosion and landslides here, so farming and conservation in the north-east must be planned carefully.