Chhath Puja or Surya Shashti is an ancient Hindu festival dedicated to the Hindu Sun God, Surya.
The Chhath Puja is performed in order to thank Surya for sustaining life on earth and to request the granting of certain wishes.
The rituals of the festival are rigorous and are observed over a period of four days. They include holy bathing, fasting and abstaining from drinking water (Vratta), standing in water for long periods of time, and offering prashad (prayer offerings) and aragh to the setting and rising sun.
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