Read the other Great Myths here

Here, in order, are the ends and springs
Of gloomy earth and misty Tartarus,
And of the barren sea and starry heaven,
Murky and awful, loathed by the very gods.
There is the yawning mouth of hell, and if
A man should find himself inside the gates,
He would not reach the bottom for a year;
Gust after savage gust would carry him
Now here, now there. Even the deathless gods
Find this an awesome mystery. Here, too,
Is found the fearsome home of dismal Night
Hidden in dark blue clouds. Before her house
The son of Iapetos, unshakable,
Holds up broad heaven with his head and hands
Untiring, in the place where Night and Day
Approach and greet each other, as they cross
The great bronze threshold. When the one goes in,
The other leaves; never are both at home,
But always one, outside, crosses the earth,
The other waits at home until her hour
For journeying arrives. The one brings light
All-seeing, to the earth, but deadly Night,
The other, hidden in dark clouds, brings Sleep,
Brother of Death, and carries him in her arms.
There live the children of dark Night, dread gods,
Sleep and his brother Death. The shining Sun
Has never looked upon them with his rays
Not going up to heaven, nor coming back.
The one of them is kind to men and goes
Peacefully over earth and the sea’s broad back;
The other’s heart is iron; in his breast
Is pitiless bronze: if she should touch a man,
That man is his. And even to the gods
Who are immortal, Death is an enemy.

– Hesiod, Theogony, tr. Dorothea Wender