Poseidon(puh-Sye-dun or poh-Sye-dun), the god of the sea, was the son of the Titans, Chronus and Rhea, and the brother of Zeus and Hades. His sisters were Demeter, Hestia, and Hera, and he was second only to Zeus in power and eminence. Although he was most often seen at Olympus, he had a great palace beneath the sea.
Poseidon was in complete control of his realm. Peaceful waters followed the smooth wheels of his golden chariot in which he rode, smashing and destroying with his trident whatever he pleased. He was revered by all Agean seamen.
One major story about Poseidon concerns the creation of the first horse. He and Athena were in a dispute over the naming of a city. The gods decreed that Poseidon and Athena would each create something, and the one whose creation was judged by the gods as being most useful to man, would have the city named after them. Poseidon struck the ground with his trident, and from that spot leapt a horse; Athena created the olive tree, and the gods judged in favor of Athena, thus the city's name is Athens.