The Himalayas are the highest young fold mountains in the world.
The word Himalaya comes from Sanskrit.
Him means snow and Alay means abode or house.
So, Himalaya means House of Snow.
The Himalayas form one of the most important physical features of India. They act as a physical barrier, climatic barrier, drainage divide, and cultural divide.
The world’s highest mountain peak, Mount Everest, is also situated in the Himalayan range.
Table of Contents
Importance Of The Himalayas
The Himalayas are not just mountains.
They influence India’s climate, river systems, settlement patterns, agriculture, defence, and cultural geography.
They are important because:
- They protect the Indian subcontinent from cold winds coming from Central Asia.
- They help in the development of the Indian monsoon system.
- They give rise to major perennial rivers.
- They act as a natural frontier in the north.
- They contain glaciers, passes, valleys, and high peaks.
- They support rich biodiversity and diverse tribal communities.
Origin Of The Himalayas
The Himalayas were formed because of the collision between the Indian Plate and the Eurasian Plate.
Before the Himalayas were formed, the Indian and Eurasian landmasses were separated by a shallow sea called the Tethys Sea.
Due to plate movement, the Indian Plate moved northwards.
About 40 to 50 million years ago, the Indian landmass collided with the Eurasian landmass.
The sediments deposited in the Tethys Sea were compressed, folded, and uplifted.
This process gave rise to the mighty Himalayan mountain system.
Himalayas As Young Fold Mountains
The Himalayas are called young fold mountains because:
- They were formed relatively recently in geological history.
- They were formed by folding of sediments.
- They are still rising due to ongoing plate movement.
- They are tectonically active.
- They are affected by faults, folds, and thrusts.
- Earthquakes are common in the Himalayan region.
General Direction Of The Himalayas
The Himalayas consist of a series of parallel mountain ranges.
Their direction changes from region to region.
- In north-western India, the general direction is from north-west to south-east.
- In Darjeeling and Sikkim, the ranges run in an east-west direction.
- In Arunachal Pradesh, they run from south-west to north-west.
- In Nagaland, Manipur, and Mizoram, they run in a north-south direction.
Syntaxial Bending Of The Himalayas
The Himalayas bend sharply at both ends.
These bends are called syntaxial bends.
- The western syntaxial bend is near Nanga Parbat.
- The eastern syntaxial bend is near Namcha Barwa.
From west to east, the width of the Himalayas decreases, while their height increases comparatively.
Himalayan Mountain Ranges
From north to south, the Himalayas consist of four major ranges:
- Trans Himalayas / Tibetan Himalayas
- Great Himalayas / Inner Himalayas / Himadri
- Lesser Himalayas / Himachal / Middle Himalayas
- Shiwalik Range / Outer Himalayas
1. Trans Himalayas
The Trans-Himalayan Mountain Region lies to the north of the Great Himalayas.
It consists of:
- Karakoram Range
- Ladakh Range
- Zanskar Range
- Kailash Range
These ranges emerged from the Pamir Knot.
They were lifted much before the Himalayas, between the Jurassic and Cretaceous periods.
Geologically, they are not considered part of the Himalayas.
Important Features Of Trans Himalayas
- The Karakoram Range has K2 or Godwin Austen, the highest peak of India.
- Siachen Glacier is known as the highest battlefield.
- Baltoro Glacier is the largest mountain glacier.
- The highest point of the Ladakh Range is Rakaposhi.
- The extension of the Ladakh Range in Tibet is called the Kailash Range.
- The Indus River originates from the Kailash region.
- The highest point of the Zanskar Range is Nanga Parbat.
- The Ladakh Plateau is a cold desert.
- The region mostly receives rainfall during winter.
2. Great Himalayas Or Himadri
The Great Himalayas are also called:
- Inner Himalayas
- Himadri
This is the most continuous Himalayan range.
It contains the loftiest Himalayan peaks.
Its average height is about 6,000 metres.
Important Peaks Of The Great Himalayas
| Peak | Location | Height |
|---|---|---|
| Mount Everest | Nepal | 8,848.86 metres |
| Kanchenjunga | India | 8,586 metres |
| Makalu | Nepal | 8,485 metres |
| Dhaulagiri | Nepal | 8,167 metres |
| Nanga Parbat | India | 8,126 metres |
| Annapurna | Nepal | 8,091 metres |
| Nanda Devi | India | 7,817 metres |
| Namcha Barwa | Eastern Himalayas | 7,782 metres |
3. Lesser Himalayas Or Himachal
The Lesser Himalayas lie south of the Himadri.
They are also called:
- Himachal
- Middle Himalayas
They are made of highly compressed and altered rocks.
Their altitude varies from 3,700 metres to 4,700 metres.
Their average width is about 50 Km.
Important Ranges Of Lesser Himalayas
| Range | Region |
|---|---|
| Pir Panjal Range | Jammu and Kashmir |
| Dhauladhar Range | Himachal Pradesh |
| Mussoorie Range and Nag Tibba Range | Uttarakhand |
| Mahabharat Range | Nepal |
The Pir Panjal Range is the longest range of the Lesser Himalayas.
Valleys And Hill Stations In Lesser Himalayas
The Lesser Himalayas are known for beautiful valleys and hill stations.
Important valleys include:
- Kashmir Valley
- Kullu Valley
- Kangra Valley
Important hill stations include:
- Nainital
- Almora
- Kausani
- Ranikhet
- Shimla
- Dharamshala
- Dalhousie
- Manali
- Kasauli
- Srinagar
- Gulmarg
4. Shiwalik Range Or Outer Himalayas
The Shiwaliks are the outermost range of the Himalayas.
They are also called the Outer Himalayas.
They extend over a width of about 10 to 15 Km.
Their altitude varies between 900 metres and 1,100 metres.
They are made of unconsolidated sediments brought down by rivers from the higher Himalayan ranges.
These sediments include:
- Sand
- Silt
- Gravel
- Stones
- Debris
Regional Names Of Shiwaliks
| Region | Name Of Shiwaliks |
|---|---|
| Jammu Region | Jammu Hills |
| Arunachal Pradesh | Dafla Hills, Miri Hills, Abor Hills and Mishmi Hills |
| Uttarakhand | Dhang Range, Dundwa Range |
| Nepal | Churia Ghat Hills |
Duns And Duars
Between the Shiwaliks and the Lesser Himalayas, longitudinal valleys are found.
In the western Himalayas, these valleys are called Duns or Doons.
In the eastern Himalayas, similar formations are called Duars.
Formation Of Duns
The Shiwalik hills were formed by the accumulation of conglomerates such as sand, stone, silt, gravel, and debris.
In the initial stage, these deposits blocked the courses of rivers flowing down from higher Himalayan regions.
This led to the formation of temporary lakes.
Over time, more sediments were deposited in these lakes.
Later, rivers cut through the deposits and drained the lakes.
The remaining flat valleys came to be known as Duns.
Important Duns
- Dehra Dun
- Kotli Dun
- Patli Dun
- Jammu Dun
- Pathankot Dun
- Kotah
- Patli Kothri
- Chumbi
- Kyarda
- Chaukhamba
- Udhampur
Dehra Dun is the best-known example.
It is about 75 Km long and 15 to 20 Km wide.
Regional Division Of The Himalayas
On the basis of relief, alignment of ranges, and other geomorphological features, the Himalayas can be divided into five regions:
- Kashmir or Northwestern Himalayas
- Himachal and Uttarakhand Himalayas
- Darjeeling and Sikkim Himalayas
- Arunachal Himalayas
- Eastern Hills and Mountains
1. Kashmir Or Northwestern Himalayas
This region includes ranges such as:
- Karakoram
- Ladakh
- Zanskar
- Pir Panjal
The north-eastern part of the Kashmir Himalayas is a cold desert.
It lies between the Greater Himalayas and the Karakoram Range.
The world-famous Kashmir Valley lies between the Greater Himalayas and the Pir Panjal Range.
Important glaciers such as Baltoro and Siachen are found in this region.
Important Features Of Kashmir Himalayas
- The region is famous for Karewa formations.
- Karewas are thick deposits of glacial clay and other materials embedded with moraines.
- Karewas are useful for saffron cultivation.
- Important freshwater lakes include Dal Lake and Wular Lake.
- Important saltwater lakes include Pangong Tso and Tso Moriri.
- The region is drained by the Indus, Jhelum and Chenab rivers.
- Important pilgrimage places include Vaishno Devi, Amarnath and Charar-e-Sharief.
Important Passes Of Kashmir Himalayas
- Khardung La – Ladakh Range.
- Zoji La – Great Himalayas.
- Banihal – Pir Panjal Range.
- Photu La – Zanskar Range.
2. Himachal And Uttarakhand Himalayas
This part of the Himalayas lies between the Ravi River in the west and the Kali River in the east.
It is drained by two major river systems:
- Indus system
- Ganga system
Important rivers of this region include:
- Ravi
- Beas
- Sutlej
- Yamuna
- Ghaghara
The three Himalayan ranges – Himadri, Himachal, and Shiwalik – are clearly visible in this region.
Important Features
- Dhauladhar is important in Himachal Pradesh.
- Nag Tibba is important in Uttarakhand.
- Important hill stations include Dharamshala, Mussoorie, and Shimla.
- Dehra Dun is a major distinguishing feature.
- The Valley of Flowers is located in this region.
- Important pilgrimage places include Gangotri, Yamunotri, Kedarnath, Badrinath, and Hemkund Sahib.
- The region is also known for five famous Prayags, or river confluences.
3. Darjeeling And Sikkim Himalayas
This region lies between the Nepal Himalayas in the west and the Bhutan Himalayas in the east.
It is relatively small, but very important.
Important Features
- Fast-flowing rivers such as Tista are found here.
- Kanchenjunga, the third-highest mountain peak in the world, is located in this region.
- Higher areas are inhabited by Lepcha tribes.
- Southern Darjeeling Himalayas have a mixed population of Nepalis, Bengalis, and tribal communities from Central India.
- The region has moderate slopes, thick soil cover, high organic content, well-distributed rainfall, and mild winters.
- These conditions helped the British introduce tea plantations.
- Shiwalik formations are absent here.
- The region is important for Duar formations, which are used for tea plantations.
4. Arunachal Himalayas
The Arunachal Himalayas extend from the east of the Bhutan Himalayas up to Diphu Pass.
Important peaks include:
- Kangtu
- Namcha Barwa
Rivers Of Arunachal Himalayas
The ranges are cut by fast-moving rivers flowing from north to south.
These rivers form deep gorges.
Important rivers include:
- Subansiri
- Kameng
- Dihang
- Dibang
- Lohit
These rivers are perennial and have a high rate of fall.
This gives the region very high hydroelectric power potential.
Tribal Communities
The Arunachal Himalayas are home to many ethnic tribal communities.
Important communities include:
- Monpa
- Daffla
- Abor
- Mishmi
- Nishi
- Nagas
Many communities practise Jhum cultivation, also called shifting cultivation.
5. Eastern Hills And Mountains
The Eastern Hills and Mountains run through the northeastern states.
They are mostly composed of strong sandstones, which are sedimentary rocks.
They are covered with dense forests and mostly run as parallel ranges and valleys.
Important Hill Ranges
- Patkai Bum
- Naga Hills
- Manipur Hills
- Mizo Hills
- Lushai Hills
These are low hills inhabited by many tribal groups practising Jhum cultivation.
Drainage Of Eastern Hills
- The Barak River is important in Manipur and Mizoram.
- Most rivers in Nagaland form tributaries of the Brahmaputra.
- Rivers of Mizoram and Manipur are tributaries of the Meghna.
- Rivers in eastern Manipur are tributaries of the Chindwin, which joins the Irrawaddy system of Myanmar.
Mizoram is also known as the Molassis Basin, made of soft unconsolidated deposits.
Shifting Cultivation
Shifting cultivation is a traditional farming method practised in hilly and forested regions.
In this system, people clear and burn a patch of land, cultivate it for a few years, and then move to a new area.
The old land is left to regenerate naturally.
In North-East India, it is known as Jhum.
Names Of Shifting Cultivation In India
- Jhumming or Jhum – North-East India.
- Podu – Andhra Pradesh.
- Bewar / Dahiya – Madhya Pradesh.
- Kumari – Western Ghats.
- Ponam – Kerala.
- Batra – South-eastern Rajasthan.
- Koman / Bringa – Odisha.
- Khil – Himalayan belt.
- Kuruwa – Jharkhand.
Names Of Shifting Cultivation In Other Countries
| Name | Region |
|---|---|
| Ray | Vietnam |
| Tavy | Madagascar |
| Masole | Congo Basin |
| Fang | Equatorial African countries |
| Logan | Western Africa |
| Comile | Mexico |
| Milpa | Yucatán, Mexico and Guatemala |
| Echalin | Guadeloupe |
| Conuco / Konuko | Venezuela |
| Roka / Roca | Brazil |
| Chitemene / Chetemini | Uganda, Zambia and Zimbabwe |
| Caingin | Philippines |
| Taungya | Myanmar |
| Chena | Sri Lanka |
| Ladang | Java and Indonesia |
| Tamrai | Thailand |
| Huma / Humah | Java and Indonesia |
Faults In The Himalayas
A fault is a fracture or zone of fractures between two blocks of rock.
Faults allow rock blocks to move relative to each other.
This movement may be:
- Sudden, causing earthquakes.
- Slow, known as creep.
Faults may range from a few millimetres to thousands of kilometres.
How Is A Fault Created?
A new fault forms when stress on rocks becomes strong enough to cause a fracture.
One side of the fracture then moves relative to the other.
This movement may be caused by compressional or tensional forces.
The Himalayas are young fold mountains formed by the collision of the Indian Plate and the Eurasian Plate.
This collision produced major thrusts and faults running almost parallel to the mountain range from west to east.
Major Thrusts And Faults Of The Himalayas
Main Frontal Thrust / Himalayan Frontal Fault
The Main Frontal Thrust, or MFT, is the youngest and southernmost major thrust fault.
It separates the Himalayan foothills or Shiwaliks from the Indo-Gangetic Plain.
It is the surface expression of the Main Himalayan Thrust.
It accommodates a major part of the present-day convergence between the Indian and Eurasian plates.
Seismic activity along this fault is responsible for major earthquakes in the Himalayan region.
Main Boundary Thrust
The Main Boundary Thrust, or MBT, separates the Lesser Himalayas from the Sub-Himalayas or Shiwaliks.
It was active during the Miocene period.
Though less active than the Main Frontal Thrust today, it remains part of the seismically active Himalayan fault system.
Main Central Thrust
The Main Central Thrust, or MCT, separates the Lesser Himalayas from the Greater Himalayas.
It is a ductile shear zone.
Along this zone, high-grade metamorphic rocks of the Greater Himalayas were pushed over low-grade rocks of the Lesser Himalayas.
It played an important role in the uplift and formation of the Greater Himalayas.
Indus-Tsangpo Suture Zone
The Indus-Tsangpo Suture Zone, or ITSZ, is the northernmost major compressional fault line.
It represents the actual collision zone between the Indian and Eurasian plates.
It extends for thousands of kilometres and marks the boundary between the Tibetan Plateau and the Greater Himalayas.
It also represents the final closing of the Tethys Sea and the beginning of Himalayan mountain formation.
Seismic Gap
A seismic gap is a part of an active fault that has not experienced a major earthquake recently, unlike nearby segments of the same fault.
Stress accumulates in these gaps for long periods.
This creates the possibility of future earthquakes.
Three Main Seismic Gaps In The Himalayas
- Assam Gap – Between the 1950 Assam earthquake and 1934 Bihar-Nepal earthquake rupture zones.
- Central Gap – Between the 1905 Kangra earthquake and 1934 Bihar-Nepal earthquake rupture zones.
- Kashmir Gap – West of the 1905 Kangra earthquake rupture zone.
Important Passes In Himalayan Region
| Mountain Pass | State / UT | Features |
|---|---|---|
| Chang La | Ladakh | Connects Leh to Pangong Lake |
| Khardung La | Ladakh | Gives access to Nubra Valley and supports Siachen supply route |
| Tanglang La | Ladakh | High-altitude pass on Leh-Manali Highway |
| Zoji La | Jammu and Kashmir | Connects Kashmir Valley with Ladakh |
| Karakoram Pass | Ladakh | Historic trade route connecting India and Central Asia |
| Pensi La | Ladakh | Connects Kargil to Zanskar |
| Banihal Pass | Jammu and Kashmir | Across Pir Panjal range |
| Pir Panjal Pass | Jammu and Kashmir | Part of Mughal Road |
| Rohtang Pass | Himachal Pradesh | Connects Kullu Valley with Lahaul-Spiti |
| Baralacha La | Himachal Pradesh | Connects Lahaul district with Ladakh |
| Shipki La | Himachal Pradesh | India-Tibet border pass in Kinnaur |
| Debsa Pass | Himachal Pradesh | Connects Kullu and Spiti districts |
| Mana Pass | Uttarakhand | Connects Uttarakhand with Tibet |
| Niti Pass | Uttarakhand | Historic Indo-Tibet trade route in Chamoli |
| Lipulekh Pass | Uttarakhand | Used for Kailash Mansarovar Yatra and trade |
| Traill’s Pass | Uttarakhand | Links Pindari and Milam valleys |
| Muling La | Uttarakhand | High-altitude pass connecting Uttarakhand with Tibet |
| Nathu La | Sikkim | India-Tibet border pass used for trade and strategy |
| Jelep La | Sikkim | Historic Indo-Tibet trade route |
| Diphu Pass | Arunachal Pradesh | Tri-junction of India, China and Myanmar |
| Pangsau Pass | Arunachal Pradesh | Connects Arunachal Pradesh with Myanmar |
| Sela Pass | Arunachal Pradesh | Connects Tawang with the rest of India |
Important Glaciers Of The Himalayan Mountains
| Region | Glacier |
|---|---|
| Karakoram | Siachen Glacier |
| Karakoram | Baltoro Glacier |
| Karakoram | Hispar Glacier |
| Karakoram | Biafo Glacier |
| Karakoram | Rimo Glacier |
| Karakoram | Sasser Glacier |
| Himachal Himalaya / Pir Panjal | Bara Shigri Glacier |
| Himachal Himalaya / Pir Panjal | Sonapani Glacier |
| Uttarakhand / Garhwal | Gangotri Glacier |
| Uttarakhand / Garhwal | Satopanth Glacier |
| Uttarakhand / Garhwal | Khatling Glacier |
| Uttarakhand / Garhwal | Dokriani Glacier |
| Uttarakhand / Kumaon | Milam Glacier |
| Uttarakhand / Kumaon | Pindari Glacier |
| Uttarakhand / Kumaon | Kafni Glacier |
| Sikkim / Kanchenjunga Region | Zemu Glacier |
Importance Of The Great Himalayas In Indian Geography
The Himalayas are central to India’s physical geography.
They affect:
- Climate
- Monsoon rainfall
- River systems
- Agriculture
- Natural vegetation
- Biodiversity
- Hydropower potential
- Tourism
- Pilgrimage
- Border security
- Earthquake risk
The Himalayas are also the source region for several major rivers that support the northern plains and millions of people.
Important Facts At A Glance
| Topic | Fact |
|---|---|
| Meaning of Himalaya | House of Snow |
| Type of mountain | Young fold mountain |
| Ancient sea | Tethys Sea |
| Plates involved | Indian Plate and Eurasian Plate |
| Formation period | About 40 to 50 million years ago |
| Western syntaxial bend | Nanga Parbat |
| Eastern syntaxial bend | Namcha Barwa |
| Himalayan ranges | Trans Himalaya, Himadri, Himachal, Shiwalik |
| Highest peak of India | K2 / Godwin Austen |
| Highest battlefield | Siachen Glacier |
| Largest mountain glacier | Baltoro Glacier |
| Most continuous range | Great Himalayas / Himadri |
| Average height of Himadri | About 6,000 metres |
| Longest Lesser Himalayan range | Pir Panjal |
| Outermost Himalayas | Shiwaliks |
| Largest Dun | Dehra Dun |
| Main Himalayan fault zones | MFT, MBT, MCT, ITSZ |
| Main seismic gaps | Assam Gap, Central Gap, Kashmir Gap |
FAQs On The Great Himalayas
What does Himalaya mean?
Himalaya means House of Snow. It comes from the Sanskrit words Him, meaning snow, and Alay, meaning abode or house.
How were the Himalayas formed?
The Himalayas were formed by the collision of the Indian Plate with the Eurasian Plate. Sediments of the Tethys Sea were compressed, folded, and uplifted to form the Himalayan mountains.
Why are the Himalayas called young fold mountains?
They are called young fold mountains because they were formed recently in geological history by folding of sediments and are still tectonically active.
What is the Tethys Sea?
The Tethys Sea was a shallow ancient sea that existed between the Indian and Eurasian landmasses before the formation of the Himalayas.
What are the four Himalayan ranges from north to south?
The four ranges are Trans Himalayas, Great Himalayas or Himadri, Lesser Himalayas or Himachal, and Shiwaliks.
What are the Trans Himalayas?
The Trans Himalayas lie north of the Great Himalayas and include the Karakoram, Ladakh, Zanskar, and Kailash ranges.
Which is the highest peak of India?
K2, also called Godwin Austen, is the highest peak of India.
Which is the highest battlefield in the world?
Siachen Glacier is known as the highest battlefield.
Which is the largest mountain glacier mentioned in the chapter?
Baltoro Glacier is mentioned as the largest mountain glacier.
What is Himadri?
Himadri is the Great or Inner Himalaya. It is the most continuous Himalayan range and contains many of the highest peaks.
What is the Lesser Himalaya?
The Lesser Himalaya, also called Himachal, lies south of the Himadri and includes ranges such as Pir Panjal, Dhauladhar, Mussoorie, Nag Tibba, and Mahabharat.
Which is the longest range of the Lesser Himalayas?
The Pir Panjal Range is the longest range of the Lesser Himalayas.
What are Shiwaliks?
The Shiwaliks are the outermost Himalayan range, made of unconsolidated sediments brought by rivers from higher Himalayan ranges.
The Shiwaliks are the outermost Himalayan range, made of unconsolidated sediments brought by rivers from higher Himalayan ranges.
The Shiwaliks are the outermost Himalayan range, made of unconsolidated sediments brought by rivers from higher Himalayan ranges.
What are Duns?
Duns are longitudinal valleys located between the Shiwalik and Lesser Himalayan ranges.
Which is the largest Dun?
Dehra Dun is the largest and best-known Dun.
What are Karewa formations?
Karewas are thick deposits of glacial clay and other materials found in the Kashmir Himalayas. They are useful for saffron cultivation.
What is Jhum cultivation?
Jhum cultivation is shifting cultivation practised mainly in North-East India.
What is a fault?
A fault is a fracture or zone of fractures between two blocks of rock, allowing movement between them.
What is the Main Frontal Thrust?
The Main Frontal Thrust is the youngest and southernmost major thrust fault, separating the Shiwaliks from the Indo-Gangetic Plain.
What is the Indus-Tsangpo Suture Zone?
It is the northernmost major compressional fault line and marks the collision zone between the Indian and Eurasian plates.
What is a seismic gap?
A seismic gap is a part of an active fault that has not experienced a major earthquake recently and may accumulate stress for future earthquakes.
What are the main seismic gaps in the Himalayas?
The main seismic gaps are Assam Gap, Central Gap and Kashmir Gap.
Which pass is used for Kailash Mansarovar Yatra?
Lipulekh Pass in Uttarakhand is used for Kailash Mansarovar Yatra.
Which pass connects Tawang with the rest of India?
Sela Pass in Arunachal Pradesh connects Tawang with the rest of India.
Last Moment Exam Cheat Sheet – The Great Himalayas
- Himalaya meaning – House of Snow.
- Himalayas – Highest young fold mountains of the world.
- Mount Everest – Highest peak of the world, located in Himalayan range.
- Himalayas act as – Physical, climatic, drainage and cultural divide.
- Tethys Sea – Ancient sea between Indian and Eurasian landmasses.
- Himalayas formed by – Collision of Indian Plate and Eurasian Plate.
- Formation period – About 40 to 50 million years ago.
- Western syntaxial bend – Nanga Parbat.
- Eastern syntaxial bend – Namcha Barwa.
- From west to east – Width decreases and height increases comparatively.
- Himalayan ranges from north to south – Trans Himalaya, Himadri, Himachal, Shiwalik.
- Trans Himalayas include – Karakoram, Ladakh, Zanskar and Kailash ranges.
- Trans Himalayas emerged from – Pamir Knot.
- K2 / Godwin Austen – Highest peak of India.
- Siachen Glacier – Highest battlefield.
- Baltoro Glacier – Largest mountain glacier.
- Ladakh Plateau – Cold desert.
- Himadri – Great or Inner Himalaya.
- Average height of Himadri – About 6,000 metres.
- Kanchenjunga – 8,586 metres, India.
- Lesser Himalaya – Also called Himachal or Middle Himalaya.
- Pir Panjal – Longest range of Lesser Himalayas.
- Shiwalik – Outermost range of Himalayas.
- Shiwalik altitude – 900 to 1,100 metres.
- Duns – Longitudinal valleys between Shiwalik and Lesser Himalayas.
- Largest Dun – Dehra Dun.
- Kashmir Himalayas – Famous for Karewa formations and saffron cultivation.
- Important Kashmir lakes – Dal, Wular, Pangong Tso, Tso Moriri.
- Himachal-Uttarakhand Himalayas – Between Ravi and Kali rivers.
- Darjeeling-Sikkim Himalayas – Known for Kanchenjunga, Tista and tea plantations.
- Arunachal Himalayas – Extend up to Diphu Pass.
- Important Arunachal rivers – Subansiri, Kameng, Dihang, Dibang, Lohit.
- Eastern Hills – Patkai Bum, Naga Hills, Manipur Hills, Mizo/Lushai Hills.
- Jhum – Shifting cultivation in North-East India.
- MFT – Separates Shiwaliks from Indo-Gangetic Plain.
- MBT – Separates Lesser Himalayas from Shiwaliks.
- MCT – Separates Lesser Himalayas from Greater Himalayas.
- ITSZ – Actual collision zone of Indian and Eurasian plates.
- Seismic gaps – Assam Gap, Central Gap, Kashmir Gap.
- Nathu La – Sikkim pass used for trade and strategic purposes.
- Lipulekh Pass – Used for Kailash Mansarovar Yatra.
- Sela Pass – Connects Tawang with the rest of India.