Greek God of the Sea, Earthquakes, & Horses

He is the second son of the Titans Cronus and Rhea, and brother of Zeus, Hades, Hera, Demeter, and Hestia.

Consorts & Children:
By his wife, the sea-goddess Amphitrite, he's the father of Triton, a merman, though he's also said to have fathered the mythical Pegasus (by Medusa), the cyclops Polyphemus, the legendary hunter Orion, and Theseus, the hero who defeated the Minotaur.

Sacred Symbols:
He is often depicted holding a trident, and riding a chariot drawn by hippocampi, or sea-horses. His sacred animals are horses, fishes, and dolphins.

Poseidon Around the World:
His Roman counterpart is Neptune, though he also has a Norse equivalent in Njordr.

SOURCES: Greek Mythology.com, MythWeb, Encyclopedia Mythica, & Wikipedia