▁to ▁collect ▁rain water ▁during ▁season al ▁mon so ons . ▁While ▁many ▁such ▁structures ▁are ▁util itar ian ▁in ▁construction , ▁they ▁sometimes ▁include ▁significant ▁architect ural ▁emb ell ish ments , ▁as ▁in ▁the ▁Ad al aj ▁step well , ▁which ▁attract s ▁a ▁large ▁number ▁of ▁tour ists . ▁In ▁the ▁past , ▁these ▁step well s ▁were ▁frequ ented ▁by ▁trav ellers ▁and ▁car av ans ▁as ▁stop o vers ▁along ▁trade ▁routes . ▁ ▁The ▁first ▁rock - cut ▁step ▁well s ▁in ▁India ▁are ▁dated ▁from ▁ 2 0 0 - 4 0 0 ▁AD . ▁Sub sequently , ▁the ▁well s ▁at ▁D h ank ▁( 5 5 0 - 6 2 5 ) ▁and ▁construction ▁of ▁stepped ▁p onds ▁at ▁B hin mal ▁( 8 5 0 - 9 5 0 ) ▁took ▁place . ▁ ▁The ▁city ▁of ▁Moh en jo - d aro ▁has ▁well s , ▁which ▁may ▁be ▁the ▁prede cess or ▁of ▁the ▁step ▁well ; ▁as ▁many ▁as ▁ 7 0 0 ▁well s ▁have ▁been ▁discovered ▁in ▁just ▁one ▁section ▁of ▁the ▁city , ▁leading ▁sch ol ars ▁to ▁believe ▁that ▁' cy l ind rical ▁brick ▁l ined ▁well s ' ▁were ▁invent ed ▁by ▁the ▁people ▁of ▁the ▁Ind us ▁Valley ▁Civil ization . ▁Between ▁third ▁and ▁second ▁mill en ni um ▁BC , ▁at ▁the ▁' Gre at ▁Bath ', ▁at ▁the ▁site ▁of ▁Moh en j od aro ▁of ▁the ▁Har app an ▁civil