The Atlantic Ocean (literally “the Ocean of Atlas”) was known to Greeks since the time of Homer, but the term did not come into use until the 5th century bce, because of mythological associations of the giant Atlas with the far western Mediterranean. Phoenicians were the first to sail on the ocean, perhaps as early as the beginning of the first millennium bce, and Greeks first went beyond the Pillars of Heracles into the Atlantic in the latter 7th century bce. Much of the early Greek exploration of the Atlantic was due to Massalians, who by 500 bce had gone south of the Pillars into the tropics, and north perhaps to the British Isles, primarily seeking trade connections. The Carthaginians also went beyond the Pillars, even farther than the Massalians, but their explorations were only vaguely known to the Graeco-Roman world until 146 bce. The greatest Greek explorer of the Atlantic was Pytheas of Massalia, who in the latter 4th century bce explored the British Isles and headed north into the Arctic, discovering Thule (probably Iceland), and reaching the Norwegian coast. After the fall of Carthage, the South Atlantic was open to Greeks (and eventually Romans). Polybius of Megalopolis went to the equatorial regions, and Eudoxus of Cyzicus attempted to perfect a route to India around the continent of Africa. The Atlantic islands were also explored, in part. There is evidence for contact with the Madeiras and Canaries, and less certain information about the Cape Verdes and Azores. There is, however, no reliable evidence that anyone from Graeco-Roman antiquity crossed the Atlantic and returned to report on it: casual finds of antiquities in the New World are generally dismissed. Yet exploration of the Atlantic led to the development of tidal theories—tides in the Mediterranean are minimal—first by Pytheas, and then later by Poseidonius and others. The Romans added little to ancient knowledge of the Atlantic, although they explored the region between the British Isles and Scandinavia, which they named the North Sea. But a series of maritime disasters in the early 1st century ce led the Romans to abandon travel on the ocean, and nothing more was discovered until medieval times.