In early Greek cosmology, the earth is a flat, central region surrounded by fantastical creatures, monsters, and quasi-humans at the edges of the earth. The edge was believed to be surrounded by a cosmic ocean, personifying the god
Oceanus. The outer edge of the cosmic ocean, Oceanus, is said to be overlaid by the rim of a shield created by Hephaistos, fashioned originally for
Achilles. The cosmic ocean beyond the edges of the earth is also found in other Near Eastern cosmologies, as shown by the
Babylonian Map of the World. However, in the Babylonian cosmos, the ocean surrounding the earth extends indefinitely and does not have an end. In the early Greek cosmos, Oceanus is a river and has an outer bank. Beyond the outer bank is a second terrestrial area which can be walked on. In the writings of Hesiod, several beings are located in this outer terrestrial area, such as the
Hesperides and
Gorgons. The only human said to have reached this area is
Heracles, during his journey to find the cattle of
Eurytion. This outer region, known as Hades, is also not illuminated by the sun, which only circles above the main terrestrial region inhabited by humans. Hades is spatially described using the Greek words
erebos and
zophos, which designate a region of darkness unreached by the sun. According to
Mimnermus, during the night, the sun lies in a golden chamber located at the banks of the ocean, or perhaps, ends up resting in a
barque made by
Hephaistos. According to the Homeric literature, the sun rises from Oceanos in the morning and plunges into it at night. An Athenian wine-bowl from c. 430 BC depicts the sun-god Helios being pulled out of the ocean in a chariot driven by winged horses, with stars in the background of the scene setting into the water. The world terrain that lies past the cosmic ocean Oceanus is known as
Hades (the afterworld, not to be confused with
Tartarus or the netherworld), which is where all humans go to after death. In other words, Oceanus was the body of water that separated the domains of the living and the dead. In addition, this also implies that in the Greek cosmology, the domains of the living and the dead are on the same horizontal plain, as opposed to a vertical one (meaning that the dead are 'besides' the living, and not in a domain below them). This is reflected by the journey of
Odysseus to the afterworld. Odysseus crosses the river ocean, takes a long walk across the banks of the ocean, and then arrives at the place where the rivers
Cocytus and
Phlegethon join to form the
Acheron. The center of the Earth (
axis mundi) is often said to have a cosmic mountain (similar to
Mount Mashu in Mesopotamian cosmology) or
cosmic tree. In Homer's Iliad,
Mount Olympus is the cosmic mountain, and it reaches all the way up to heaven. The island of
Circe functions as a gate that anyone must go through in order to enter Hades from the living world, or to go through if they wish to leave Hades and return to the living world. This island, also called "the dwelling of early Dawn and her dancing-lawns, and the risings of the sun" (
Odyssey, Book 12), is near the rising and setting place of the sun. This leads to a paradoxical or counter-intuitive topography where both east and west ultimately collapse into a single point, which disorients Odysseus when he reaches the island, and he says, "we do not know where East is, nor where the bright sun goes down under the earth" (that is, Odysseus cannot tell apart east from west). Like in Egyptian literature, the exit and entry point of the sun into the inhabited world, circumscribed by Oceanus, lie side by side with each other as a double-gate. Likewise in Hesiod's
Theogony (lines 750–756), the paths of the sun and moon are contiguous. == Heaven ==