The daughter of Triopas, who in his turn was the son of Poseidon and Canace. Iphimedeia was married to Aloeus, but fell desperately in love with her grandfather, and would walk up and down the beach to get him to come to her. When he never came, Iphimedeia splashed sea water on her genitals, and so became pregnant with twins, the Aloeidae : Otus and Ephialtes.
The twins grew bigger and stronger, and finally were so huge they even worried the gods. They managed to capture Ares and put him in chains, and threatened they would instigate war on the gods.
When their sister Pancratis was abducted and taken to Strongyle (Naxos) by pirates the Aloeidae were soon there to rescue her.
The brothers loved the Muses, and by Mt. Helicon they built a temple and made sure people worshipped them there.
They did, however, go too far one day. They were determined to sleep with Hera and Artemis, but the latter goddess sent a stag between them. As the twins threw heir spears at the beast they both missed, and killed each other instead.
Iphimedeias tomb lie in Anthedon and she was worshipped in Caria.