The Ganga has had religious importance since ancient times. Today, it is the holiest river in Hinduism and is, perhaps, the most religiously significant river in the world. Tirthas, or sacred pilgrimage sites, are located throughout India, but those along the Ganga are especially important. Pilgrims attend bathing festivals (melas) annually, but the largest is held once every dozen years when hundreds of thousands immerse themselves in the Ganga near Allahabad.
In addition to bathing in the Ganga, Hindus place flowers and diyas (clay dishes filled with candles) in the river. They also take small vials of river water (ganga jal) home for use in rituals.
The religious significance of the river isn't limited to bathing. In the belief that it will bring the spirits of the dead closer to moksha, Hindus throw the ashes of their deceased relatives in the Ganga. Cremation temples (ghats) line the banks of the Ganga in many places.