The Ajanta caves are incredible for their exquisite paintings; the architecture is not as impressive as that at Ellora. Built in two phases, 200 B.C. to 100 A.D. and from 400 A.D. to 600 A.D., these Buddhist caves were carved into the side of a river gorge. They worked top down and outside in, carving the black basalt, then they coated the carvings with plaster and detailed paintings. They were lost until rediscovery in 1819. See blog at https://davidkotz.org/2009/01/24/ellora-ajanta/.