The Olympian god Poseidon is the father of Pegasus. Pegasus was caught by the Greek hero Bellerophon near the fountain Peirene with the help of Athena and Poseidon. Pegasus allowed Bellerophon to ride him in order to defeat the monstrous Chimera and many other exploits. Bellerophon later fell from the winged horse's back while trying to reach Mount Olympus, home of the Gods, but he failed so Zeus transformed Pegasus into the eponymous constellation.