Several years ago, a king named Sagara magically acquired sixty thousand sons. One day, King Sagara performed a ritual of worship for the good of the kingdom, the Ashwamedha yagna. One of the integral parts of the ritual was a horse, which was stolen by the jealous Indra. Sagara sent all his sons all over the earth to search for the horse. They found it in the nether-world (or Underworld) next to a meditating sage Kapila. Believing that the sage had stolen the horse, they hurled insults at him and caused his penance to be disturbed. The sage opened his eyes for the first time in several years, and looked at the sons of Sagara. With this glance, all sixty thousand were burnt to death.
The souls of the sons of Sagara wandered as ghosts since their final rites had not been performed. When Bhagiratha, one of the descendants of Sagara, son of Dilip, learnt of this fate, he vowed to bring Ganga down to Earth so that her waters could cleanse their souls and release them to heaven.
Bhagiratha prayed to Brahma that Ganga come down to Earth. Brahma agreed, and he ordered Ganga to go down to the Earth and then on to the nether regions so that the souls of Bhagiratha's ancestors would be able to go to heaven. The vain Ganga felt that this was insulting and decided to sweep the whole earth away as she fell from the heavens. Alarmed, Bhagiratha prayed to Shiva that he break up Ganga's descent.
Ganga arrogantly fell on Shiva's head. But Shiva calmly trapped her in his hair and let her out in small streams. The touch of Shiva further sanctified Ganga. As Ganga traveled to the nether-worlds, she created a different stream to remain on Earth to help purify unfortunate souls there.
The rock on which King Bhagirath is believed to have meditated, is called Bhagirath Shila and is located near the temple of Ganga. She is the only river to follow from all the three worlds - Swarga (heaven), Prithvi (earth) and, Patala (neitherworld or hell). Thus is called "Tripathagā" ( one who travels the three worlds) in Sanskrit language.
Because of Bhagiratha's efforts Ganga descended on to earth and hence the river is also known as Bhagirathi, and the term "Bhagirath prayatna" is used to describe valiant efforts or difficult achievements.
Scientists have studied the water collected from Ganga at its origin is in a pure state and even after being kept for several years, does not get contaminated.. These medicinal properties of Ganga-Jal are attributed to the medicinal secretions of herbs and mineral content which get mixed with the water.
The seven streams of Ganga are Bhagirathi, Janhvi, Bhilangana, Mandakini, Rishiganga, Saraswati and Alaknanda which merge into Ganga at Devprayag.
There are five prayags;
Vishnuprayag - Alaknanda meet Dhauli ganga
Nandprayag - Alaknanda meets Nandakini
Karnaprayag - Alaknanda meets Pindar
Rudraprayag - Alaknanda meets Mandakini
Devprayag - Alaknanda meets Bhagirathi
These three Glaciers contribute to the river Ganga
This glacier is near the Nanda Khat and other lofty peaks. Its access is very easy and is at an altitude of 3353m. Close to the glacier is an open meadow and lofty moraine made of gravel, mud and blocks of snow. The trek to the glacier starts from Kapkote, which is the last bus terminus. The trekking route is passing through waterfalls, pine forests, meadows and having magnificent views of the peaks.
The gangotri glacier is situated at a height of 4255m. It starts from Chaukhamba cluster of snow peaks near Badrinath and extends to Gaumukh
This glacier is a lateral glacier, from the center of which bubbles out the river bhilangana. It is said that a beautiful Bhil maiden tried to win the love of the meditating Shiva and having been spurned by Him dissolved into liquid, which in turn became the rive Bhilangana. The snow peaks atop the glacier are the Jogin, sphetic prishtwan, kirti stambh, barte kanta, meru etc. The sphetic prishtwan is made of white quartz which from distance dazzles like crystal white snow The trek of Khatling glacier starts from ghuttu, the last bus terminus. The entire trekking route is studded with dense green forest and delightful meadows, excellent spots for camping, dazzling waterfalls and streams