It covered approximately twenty percent of the Earth's surface and about twenty-six percent of its water surface area.
The Atlantic Ocean occupied an elongated, S-shaped basin extending longitudinally between the Americas to the west, and Eurasia and Africa to the east. As one component of the interconnected global ocean, it was connected in the north to the Arctic Ocean (which was sometimes considered a sea of the Atlantic), to the Pacific Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in the south. (Other definitions describe the Atlantic as extending southward to Antarctica.) The equator subdivides it into the North Atlantic and South Atlantic.