The main features of early Greek cosmography are shared with those found in ancient near eastern cosmology.
The basic elements of the cosmos include (a flat) earth, heaven, the sea, and the netherworld (Tartarus), the first three of which corresponded to the gods Gaia, Ouranos, and Oceanus (or Pontos).
[1] Some primary sources for early Greek cosmology include the poetry of Homer (the Iliad and the Odyssey), Hesiod (the Theogony and the Works and Days), and surviving fragments from Mimnermus.
[2] When the spherical model of the Earth was proposed, early Greek cosmology as a whole began to be replaced, although this was not immediate.
Among authors from the early Roman Empire, Strabo, Tacitus, and the Epicureans continued to accept a flat Earth.
[10] Instead, according to Mimnermus, it lies during the night in a golden chamber by the banks of the ocean, or perhaps in a barque that had been made by Hephaistos.
This spatial separation is conceived on a horizontal plain and not a vertical one, and it is reflected by the journey of Odysseus to the afterworld (in this system, the afterworld/Hades is distinct from the underworld/Tartarus).
[12] Hades is also spatially characterized by terms like erebos and zophos which designate a region of darkness unreached by the sun.
This leads to the description of a counter-intuitive topography where both east and west ultimately collapse into a single point.
According to the Theogony of Hesiod, 116–133[16]:First of all Chaos came into being, and then broad-bosomed Earth (Gaia), a firm seat of all things for ever, and misty Tartaros, deep down in broadpathed earth, and Eros, the most beautiful among the immortal gods, he who loosens our limbs, and subdues the mind and thoughtful counsel of all gods and men.
Now Earth first of all brought forth starry Ouranos, equal to herself, so that it would cover her on all sides, to be a firm seat for the blessed gods forever.
[1] One passage in the Iliad, where Zeus makes a cosmic threat against any god who dares to intervene in the Trojan War, provides more information on how heaven relates to the rest of the universe:I will seize him and hurl him down to Tartaros wrapped in mist, far away, a place where there is a pit deeper than any other, where there are iron gates and a bronze threshold,
The entities of Night, Day, Sleep, and Death effectively experience it as a house: it can be entered into and left at will.
These images are also not mutually exclusive: the Titans have an increased difficulty of escaping from Tartarus, such as to the earth, due to the depth of the gorge.
"[27] Chaos gives rise to Ouranos, Gaia, and Pontos (heaven, earth, sea) who, by association or sexual union, bring forth the rest of the gods.
[31] Hesiod's Theogony is also closely textually related to an earlier Hittite cosmological text, the Song of Kumarbi.