The religious complex of Vat Phou is of Khmer architecture and Hindu religion and is situated at the foot of a hill.
The summit, the Phou Kao, immediately commands one's attention because of its shape, identified in ancient times with the linga, the phallic symbol of Shiva, from which originated its ancient name, Lingaparvata, and its reputation as a sacred hill. The permanent spring, at the foot of the cliffs, is probably one of the main reasons that induced the ancient rulers of the area to establish a shivaist sanctuary at this location.