Atlas.
Son of the Titan Iapetus and the Oceanid Clymene, Atlast opposed Zeus in the Titans' revolt against the Olympians. As punishment he was forced to guard the pillars of heaven or to hold up the sky itself. He is variously named as the father of Calypso, the Hesperides, the Pleiades, and others.
Atlas helped Heracles to obtain the golden apples of the Hesperides, offering to fetch the apples if Heracles would assume the mantle of the sky in his stead; he had to be tricked by Heracles into resuming his burden. When Perseus, after beheading the Gorgon Medusa, was refused hospitality by Atlas, the heroed showed him the Gorgon's head, which turned him into stone. This was said to be the origin of Mount Atlas, the highest peak in the Atlas range of northwest Africa.
See also:
Heracles, Labors of
Heracles, Apples of the Hesperides
Hesperides
Perseus and Medusa
Titans and Giants