Dev Deepavali -- "The diwali of the Gods" or "LIGHT FESTIVALS OF GOD".. 
Dev means 'God'..
Deepavali or Diwali means 'Light festival'..
Diya(traditionally), candle🕯, lighting coloured bulb 💡etc use in Diwali..
Celebrates in Varanasi, Uttar Pradesh, India..the "DEV-DEEPAVALI" is the festival of lamp-lights called "Diya" and held in 'Karthik-Poornima'..
Diya -- 
Varanasi -- Historical and religious city of India situated between the rivers 'Varna' and 'Assi(Ganga)'..
Its called "KASHI" in ancient period and "BANARAS" in medieval period..
Its falls on the FullMoon "🌑" of the Hindu month of Karthik (November-December) and takes place fifteen days after Diwali..🌚
The steps of all the Ghats on the riverfront of the Ganges River, from Ravidas-Ghat at the southern end to Rajghat, are light with more than a million earthen lamps(diyas) in honour of the Ganga, "the Ganges and its presiding goddess".. 
The gods are believed to descend to earth to bathe in the Ganges on this day..
Millions of people came around the world for watch "Ganga-Aarti", for " Snan" and for spiritual peace.. !👨👩👧👦🛁image
river : the Ganga -- water of lord Shiva and therefore its water known as the "GANGAJAL", it is the most pure sacred water to worship...
Lord SHIVA tied up goddess Ganga on his hairs to save earth to her flooding capacity.. 
Dev Diwali is also known as "TRIPURA-POORNIMA-SNAN" means triworld-fullmoon-bathe, peoples bathe in the Ganga and lighting diyas for complete their worship.. 
The tradition of lighting the lamps(Diya) on the "DEV-DEEPAVALI festival day was first started at the "PANCHGANGA-GHAT" in 1985..🌋
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