(Hinduism, Sanskrit: Ganga the Ganges + puja "worship")

The Holy Day in which the sacred river Ganga (the Ganges) descended upon earth through the heavens. All Hindus worship this most holy of rivers on this day. In the Bhagavatapurana, the event is described thus:

After many thousands of years of austerities, Maharaja Bhagiratha, desiring to bring the Ganges to earth in order to purify his ancestors, was able to achieve darshana of Ganga-devi. She said, "I am very much satisfied with your austerities and am now prepared to give you benedictions as you desire. When I fall from the sky to the surface of the planet earth, the water will certainly be very forceful. Who will sustain that force?" Bhagiratha replied, "Lord Shiva is the incarnation of the Supreme Personality of Godhead, and thus he represents the Supersoul in the embodied soul. He can sustain your forceful waves upon His head."

Then Maharaja Bhagiratha approached Lord Shiva and requested Him to sustain the forceful waves of the Ganges. Lord Shiva accepted the proposal by saying, "Let it be so." Then, with great attention, he sustained the Ganges on His head, for the water of the Ganges is purifying, haveing emanated from the toes of Lord Vishnu.

Bhag., Canto 9, Ch. 9, Texts 3-14(*)

Srila Prabhupada explains thus, in the Bhaktivedanta purport:

Simply by having water from the Ganges come in contact with the ashes of their burnt bodies, the forefathers of Maharaja Bhagiratha were elevated to the heavenly planets. Therefore, what can be said of a devotee who worships mother Ganges faithfully with a determined vow? One can only imagine the benefit that accrues to such a devotee.

Because Mother Ganges emanates from the lotus toe of the Supreme Personality of Godhead, Anantadeva, she is able to liberate one from material bondage. Therefore whatever is described herewith about her is not at all wonderful.

(*) Ordinarily I would have quoted the sanskrit, too, but it would have made this a little long...