Himalayas are relatively young with unique geographical significance for India. Himalaya stretching from J&K to the North -East of India has always been a physical ,climatic ,drainage and a cultural divide .

How Himalayas are physical barrier:-

• Divides India from central Asia and thereby protected India from their direct attack through this route.
• Isolates Indian Sub-continent from the rest of Asia .

How Himalayas create cultural divide:-

• Himalayas have three distinct chain of mountains, the upper himalayas or himadri, Himachal or lesser himalayas and Shiwaliks.
• The Himadri which is very prominent in Kashmir region has many highest glaciers of the world leading to unique pattern of living.
• In Uttarakhand Siwaliks or dun formations caused some cultivation and transhumance of tribes like Bhutias.
• In sikkim and Darjeeling the Duar formation and moderate slopes  gave rise to tea cultivation here too tribes like Lepcha lead a unique way of life.
• In North East Himalayas because of rain all around the year Tropical evergreen forests predominate which are cleared by the inhabiting tribes for Jhum cultivation.

How Himalayas create climatic divide:-

• It blocks the Monsoon winds and forces them to shed their moisture causing heavy rainfall in Northern India
• It protects the Northern plains from the cold winds from the central Asia .
• Himalayas represent a long chain of  mountains that separate India from rest of Asia making India a subcontinent with its own climatic features. During winters when freezing temperatures 
  prevail in North Asia, Himalayas object these cold winds and thus preventing the Ganga plains from freezing leading to sustenance in agriculture.
• Himalayas also obstruct the South West monsoon winds thus producing rains thus helps in maintaining the monsoon nature of our climate in North India.

How Himalayas create drainage divide:-

• Himalayas is the birthplace for three major river systems the Indus, Ganga and Brahmaputra 
  river systems which are one of the longest in the world. The rivers that flow through India originate due to melting of glaciers in the upper reaches and maintained by rain in the lower reaches thus leading to many perennial rivers which are vital for agriculture.
• Also a lot of rivers forms flood plains in the lower reaches and bring alluvium which is very productive.
• The Himalayas is the abundant reservoir of Great Indian rivers such as Ganga, Indus and Brahmaputra. The snow melt in summer and precipitation in winter makes them perennial rivers. i.e, having water throughout the year. The abundant waterfall, huge snowfield and large glaciers feed these drainage systems. The Himalayan rivers give life to the northern India.