India's extraordinary stepwells

The problem they solve

In western India the monsoon delivers most of the year's rain in a few weeks, and then nothing for months. The water table falls steadily through the dry season.

A conventional well gives you a rope and a bucket at one level. A stepwell gives you a staircase that follows the water down — usable in September when the water is high and again in May when it has fallen far below the surface.

That is the entire engineering idea, and everything else follows from it.

What they became

Once you have built a large excavated structure with a staircase, you have also built the coolest public space for miles. Temperatures at the bottom of a deep stepwell run several degrees below the surface, and the shade is constant.

So they acquired functions: pavilions to rest in, shrines in the wall niches, sculpture across every surface, and a social role — particularly for women, who did the water-carrying and for whom the stepwell was one of the few sanctioned places to gather outside the house.

Who counted as the public was regulated by caste. Dalit communities were kept from wells and tanks that caste Hindus drew from — the restriction Ambedkar's satyagraha at the Chavdar tank in Mahad in March 1927 was mounted against, and that Article 17 of the Constitution abolished in 1950.

Several of the finest were commissioned by women. Rani ki Vav at Patan was built by Queen Udayamati in memory of her husband. Adalaj was begun by Rana Veer Singh of the Vaghela dynasty and completed under Mahmud Begada, who had killed him — and the story attached to its completion, in which Veer Singh's queen Rudabai agrees to marry Begada on condition that he finish the well and then takes her own life once it is done, is part of how the building is remembered.

The great ones

Rani ki Vav, Patan, Gujarat. Eleventh century, seven storeys, and more than five hundred principal sculptures — mostly Vishnu in his avatars, and a remarkable series of women's figures. Silted up for centuries, which preserved it, and excavated in the twentieth century.

Adalaj ni Vav, near Ahmedabad. Fifteenth century, five storeys, octagonal opening, and a mixture of Hindu and Islamic ornament that makes it one of the best examples of the shared architectural vocabulary of the period.

Chand Baori, Abhaneri, Rajasthan. Around three and a half thousand steps descending three sides in a geometric lattice, thirteen storeys deep, with a pavilion on the fourth. The most photographed, and the most disorientating in person.

Agrasen ki Baoli, Delhi. Off Hailey Road, a few minutes from Connaught Place, unexpectedly, at the end of a lane.

What happened to them

Piped supply and, later, borewells removed the need. Colonial administrations discouraged them as insanitary — standing water and a communal descent, in the germ theory era, looked like a problem. Many were closed, filled or abandoned; a great many silted up.

The recent turn is interesting. Groundwater depletion across western India has made recharge structures valuable again, and several stepwells have been desilted and returned to use — not as a heritage gesture but because they still work.

How this changes across regions