Around 200 women from Alwar and Tonk districts of Rajasthan took bath at famous Ramghat on the banks of Kshipra river.
The women belonged to the caste whose members traditionally worked as manual scavengers, considered at the bottom of the caste hierarchy.
The event is viewed as an occasion that washed off their "untouchability".
The initiative was conceived by Dr Bindeshwar Pathak, Founder of Sulabh Sanitation movement.
"This Kumbh ceremony should be viewed as a bold and successful step towards the egalitarian inclusion of the downtrodden in the religio-social world of the Hindus," the release quoted Pathak as saying.