Hindus across India are celebrating the 10 day-long festival of Ganesh Chaturthi, in honour of the god of wisdom and prosperity, Lord Ganesha.

Devotees place idols of the elephant-headed god in their homes or on elevated stages in public places and then immerse them in rivers, lakes or the sea. According to popular belief, Lord Ganesha blesses those who worship him on this day by removing obstacles from their lives and granting them new beginnings.

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A devotee immerses an idol of the Hindu elephant god in the Ganges in KolkataReuters
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A devotee immerses an idol of the Hindu elephant god Ganesh, the deity of prosperity, in a pond during the Ganesh Chaturthi festival in MumbaiReuters
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Indian Hindu devotees immerse a statue of the Hindu god Lord Ganesha in a river on the outskirts of Patiala during the ten-day Ganesh Chaturthi festivalAFP
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A man transports an idol of the elephant-headed Hindu god in a taxi cab in MumbaiAFP
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Devotees unload an idol of the Hindu god Ganesh, the deity of prosperity, to be immersed into the Arabian Sea in MumbaiReuters
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A devotee daubed in coloured powder takes part in the Ganesh Chaturthi festival in MumbaiReuters
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A young man carrying an idol of Ganesh slides down into a pond in the western Indian city of AhmedabadReuters
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Hindus transport a huge idol of the elephant-headed Lord Ganesh towards the sea in MumbaiAFP
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Bollywood actress Rani Mukherjee offers prayers in front of an idol of Hindu god Lord Ganesh in MumbaiAFP
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Hindus offer prayers in front of a 60ft (22m) tall idol of Lord Ganesh in HyderabadAFP
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A rainbow is seen as devotees carry a statue of Lord Ganesh, the deity of prosperity, into the Arabian Sea in MumbaiReuters
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Hindu devotees carry idols of Ganesh into the Arabian Sea at Dadar Chowpatty beach in MumbaiAFP

Traditionally, idols were made of mud and clay, so immersing them into a lake had no harmful effects. Modern idols, however, are often made of plaster of Paris, which is non-biodegradable, and insoluble in water. The immersion of thousands of plaster idols adorned with toxic paints can have negative environmental effects, so the idols are removed after the celebrations are complete.

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Indian Hyderabad Metropolitan Development Authority workers remove statues of Ganesh from the Hussain Sagar Lake after their immersionAFP
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Workers remove statues of Lord Ganesh from the Hussain Sagar Lake in HyderabadAFP