Of Mountains and Rivers
Mountains and Rivers have a very symbiotic relationship which always seem to run in the opposite directions. While a mountain represents the highest point point in a given Geography the River on the other hand forms the lowest point of the said Geography. It is the Rivers and streams running down from the mountains that create the beautiful Valleys which give humans a foothold in the precarious mountains. The Mountains on the other hands are the geographical barrier that cause the clouds to give up their moisture in the form of snow and rain and which in turn gives rise to the Rivers. And the same Rivers are constantly eroding the Mountains and carrying the fertile deposits downstream to enrich the plains with these sediments. And finally going into the Oceans which in turn give rise to Clouds which return again to the Mountains as rain again and the Hydrological cycle is completed.
The mightiest mountain Range of the Planet, the Himalaya, doesnt even let the armies of clouds of the mighty Monsoon cross its threshold and forces the Monsoon to pour down on one side of it. Hence on one side of the Himalaya we have the Great Indo Gangetic plains, fed by the Rivers created by the Himalaya, is one of the most densely populated regions on the planet and in stark contrast the other side of the Himalaya has the Tibetan Plateau, one of the least populated regions on the Planet. The same mountain Range affecting its sides in diametrically opposite ways. Such is the might of the Mountains such as the mighty Himalaya.
There a number of Rivers that originate in the Himalayan Tibetan region and all of them flow more or less south except the Yangtze. It is not only the great Rivers of the subcontinent, the Indus , the Ganges and the Brahmaputra that arise in this area. The mighty Yangtze, the Mekong, the Salween and even the Irrawaddy rises in the Kachin foothills. The number of people who live in the basins of these Rivers exceeds well over a billion. All them rely majorly on the snow melt in the Highlands and the Mountains as well as the Rainfall caused by the same Mountains.
The different parts of the Himalayas have always been classified as between certain Rivers as they provide the perfect points of separation of two parts of a whole. The same true holds for the Himalaya given as under as per the Classical classification :
The Himalaya: Extends from the bend in the Indus in Gilgit Baltistan to the great Southward bend of the Brahmaputra (Tsangpo) (~ 1400 miles / 2300 kms)
The Classical Himalayan Sub-divisions
The Western Himalaya/ Punjab Himalaya : From the bend in the Indus to the Sutlej. ( ~ 290 miles / 460 kms)
The Garhwal/Kumaun Himalaya: From the Sutlej to the Kali River. (~ 200 miles / 320 kms)
The Nepal Himalaya: From the Kali River to the Tista River. (~ 500 miles / 800 kms)
The Assam Himalaya: From Upper Tista to the great Southward bend of the Brahmaputra (Tsangpo) (~ 450 miles / 720 kms)
Other Extensions/ Separations
The Upper Indus separates the Western Himalaya from the Karakoram
The Pir Panjals : From the Neelam/ Kishanganga to the Upper Beas.
The Zanskar Range : Extends from the Karcha (Suru) River to the upper Karnali river.
On a side note the pic I have posted is of the Giri River in an area around Yashwant Nagar. as the River meanders down the Kotkhai Hills and reaches this area. This River holds a lot of importance as most of the Drinking water for the capital of Himachal Pradesh, Shimla is sourced through this River at a facility a few kms upstream at a place called Sainj. Lovely little place near Theogh where the beautiful Darbar Fort of the Rana Sahib of Theog is located right by the Giri Rive. This River meanders through Sirmour and finally goes onto merge with the Yamuna.
And little interesting fact about Shimla is that it is said that the Ridge is the exact point of the Hydrological divided between the Indus basin and the Ganga basin. What that means is that rain/snow falling on one side of the Ridge goes down and eventually joins the Satluj and the Indus and drains into the Arabian Sea. While rain/snow on the other side flows down to eventually join the Yamuna and the Ganges and finally draining into the Bay of Bengal. This makes Himachal Pradesh the only state in India which is divided between two of the planets great River basins.
Ah of Rivers and Mountains I can talk all day and all night :)
Pic from August 2017. Giri River, Near Yashwant Nagar, Himachal Pradesh