The Undavalli Caves are ancient rock-cut Hindu temples near Vijayawada, Andhra Pradesh, dating to the 4th-7th centuries CE and known for their intricate sculptures and four-story monolithic architecture, including an unfinished temple on the first floor featuring a large reclining statue of Lord Vishnu. These caves showcase Gupta architecture and blend elements of Buddhism, Jainism, and Hinduism, having transformed from a monastery into a Hindu complex under the Vishnukundina kings.