Stepwells, also called bawdi or baoli , or vaav are well

Water well

A water well is an excavation or structure created in the ground by digging, driving, boring or drilling to access groundwater in underground aquifers. The well water is drawn by an electric submersible pump, a trash pump, a vertical turbine pump, a handpump or a mechanical pump...

s or ponds in which the water can be reached by descending a set of steps. They may be covered and protected, and are often of architectural significance. It can be multi-storied also in which a bullock turns the water wheel ("rehat") to raise the water in the well to the first or second floor.

They are most common in the west of India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

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