[Skt vāpi; Gujarati vāv; Hindi baoli]
Underground architecture unique to India, typically consisting of a well and passage of descending steps. The earliest surviving structural stepwells date to the 7th century ad, although rock-cut ones exist from earlier times, and examples continued to be built into the 20th century. In 11th-century Gujarat stepwells were elaborated into an unsurpassed form of subterranean architecture.
Stepwells usually have three major parts: (1) a vertical well (Skt kūpa) with a device for hauling water up by buckets (ghaṭa yantra); (2) a passage leading down several storeys to the water; and (3) cross-constructions built at intervals in the passage to support the sidewalls from inward thrust and thus ensure the stability of the structure. These cross-constructions ranged from simple beams to elaborate multi-storey pavilions. The length and breadth of the descending passage, the depth of the well and the number of cross-constructions were dependent on local geological conditions and the depth of the water-table....