The ruler of Hyria in Boeotia, a son of Poseidon and Alcyone. He married Clonia and is by her the father of Lycus, Nycteus, Histiaea, and Orion. He commissioned the brothers Agamedes and Trophonius to build a treasure chamber. The two brothers, however, also constructed a secret entrance known only to them, which they used to rob Hyrieus' treasures.
Hyrieus noticed the thievery but was unable to determine how, and so he laid a trap. Agamedes got caught in it and even with his brother's help could not free himself. To make identification impossible and to prevent torture, Trophonius cut off Agamedes' head and took it with him.
- Hyginus. Fabulae, 195.
- Pseudo-Apollodorus. The Library iii, 10.1.
- Scholiast on Homer's Iliad xviii, 486.
- Smith, William. (1870). Dictionary of Greek and Roman Biography and Mythology. London: Taylor, Walton, and Maberly.