Māṇḍakarṇi (Sanskrit माण्डकर्णि) was a hermit, mentioned in Book III (Aranya Kanda) of Ramayana. His story is told to Rama by sage Dharmabhrit during the journey through the Dandaka forest, when Rama, standing on the bank of the forest lake, asks about the origin of wondrous music coming from unknown source.
Māṇḍakarṇi is said to have performed austere rites, by staying in a stream and feeding on nothing but air for ten thousand years. Through these rites he had gained great power, which became alarming for the Gods, and, frightened by his Tapas, they sent five loveliest Apsaras to beguile him and seduce him from his austerities and vows. The Apsaras had succeeded in their mission, and became bound to Māṇḍakarṇi as his wifes. Through his holy power he had created a wondrous palace under the waters of the lake, for the heavenly dames to enjoy and play within. The lake which contains this palace is called Panchāpsaras ([the lake of] Five Apsaras (Nymphs)). And when wanderers come to the bank of the lake, they sometimes hear heavenly strains and charming music coming from beneath the water. This, Ramanaya tells, is the sound of Apsaras playing and tinkling with their zones and bracelets for the pleasure and bliss of great hermit, who also restored his youth through his exceptional penance.[1][2][3][4][5]