Gangotri is a small town & one of the Char Dham Sites located in Uttarakhand. Also known as an abode of Ganga. The word Gangotri is a combination of two words that describe the event i.e. Ganga + Uttari, which roughly translates into Ganga descending.
According to Valmiki Ramayana १-४३-२६-
तत्र ऋषि गण गन्धर्वा वसुधा तल वासिनः
भव अंग पतितम् तोयम् पवित्रम् इति पस्पृशुः |
And asserting that the water as holy, because it descended touching the head of Shiva, the assemblages of sages, gandharva-s, and those that are residents on the plane of earth have sipped that water at that place.
According to Mahabharata- Vana Parva- Tirth Yatra Parva- Chapter 85 - Verse 97 -
यत्र गंगा महाराज स देशस्तत तपोवनम |
सिद्धक्षेत्रं च ताज्ञ्नेयं गंगातीरसमाश्रीतम ||
O great king, the region through which the Ganga flows should be regarded as a sacred asylum, and a spot of land that is on the Ganga's banks, should be regarded as one favourable to the attainment of ascetic success.
The origin of the ganga is at Gaumukh, set in the Gangotri glacier which is 19 km trek from Gangotri. But according to our scriptures, Gangotri is the place where river Ganga descended from heaven when Lord Shiva released the mighty river from his luscious locks (jatta).
Actually, King Sagar's grandson Anshuman remained unsuccessful to bring Ganga on earth and same was with his son Dilip. However, King Anshuman's grandson Bhagirath was very resolute for this task and meditated at Gangotri. After numerous years of meditation, Ganga came down from the paradise but remained in suspense in the coils of Lord Shiva's hair. Determined to bring Ganga, King Bhagirath started meditation in order to win Lord Shiva. Being pleased with it, Lord Shiva released the Ganga as three streams.
One of these streams came on the earth in the form of Bhagirathi.
According to Valmiki Ramayana, Bala Kanda - The Youthful Majesties, Sarga 43-
Ganga descends to earth by the extraordinary effort of Bhageeratha. Shiva agrees to the alighting of Ganga on His head and from where she is released into a lake called Bindusarovar, and from there she flows in 7 courses.
We all know that Ganga is the most sacred river but very few know the reason behind it. Well, according to Devi Puraana, Book 9, Chapter 6-
गङ्गे यास्यसि पश्चात्त्वमंशेन विश्वपावनी ॥ ४९ ॥
भारतं भारतीशापात्पापदाहाय पापिनाम् ।
भगीरथस्य तपसा तेन नीता सुकल्पिते ॥ ५० ॥
नाम्ना भागीरथी पूता भविष्यसि महीतले ।
Vishnu tells Ganga-
Then, O Ganga! You will go in some parts of yours, to the Bharata Bhumi, due to curse of Bhaarati(Saraswati), to become the purificator of worlds and to burn the sins of sinners.
O well armed Ganga! by Bhagiratha's penance You will be brought down, and will be known as Bhaagirathi, and will be most sanctifying on Earth.
As per Padma Purana , Ganga originated from Lord Vishnu's feet.
As per the Matsya Purana, Ganga was there before the the beginning of Vaivasvata Manavantar. But as deluge (प्रलय) happened and then she was brought back on the Earth again.
In Gangotri, you can visit-
Gangotri Temple: Gangotri temple is dedicated to Goddess Ganga and is positioned near the sacred stone known as Bhagirath Shila, where it is said that the king Bhagirath paid his homage to Lord Shiva. .
The height of the shrine is about 20 feet and white granite has been used to build it. It was originally built by the Nepalese general Amar Singh Thapa in the early 18th century and later it was reconstructed in the 20th century by the Maharaja of Jaipur.
During the winter months the temple kapat shuts down for darshan, and the presiding deity image is shifted to its winter home in Mukhwas which is also known as Mukhba. Situated in the very beautiful hill town of Harsil.
Kedar tal: A transparent lake at the altitude of 15,600ft is a wonderful creation of god and is the idyllic place for a long trek of 17km. The trek starts from Gangotri and leads you through a variety of wonders that will make you rapt and spellbound.
Bhaironghati: It is a temple of Bhairon that is just 10km away from the Gangotri. It is amongst the most popular tourist attractions in Gangotri, because it is believed that the Lord Shiva appointed Bhairon to protect the picturesque region.
Submerged Shivling: It is also popular as Jalmanga Temple. It holds a natural rock Shivling that according to the legends, where the Lord Shiva sat to hold the Ganga in his hair locks.
one would feel connected to god in the high elevation of Gangotri.
The existence of the snow clad mountains and the magical water of the river Ganges add to the purity of the destination.
It is popularly said that There is no tirtha that is like unto the Ganga, there is no god like unto Kesava, and there is none superior to Brahmanas