Aeneid - Virgil (29 BC - 19 BC)

The gates of hell are open night and day; 

Smooth the descent, and easy is the way:

but to return, and view the cheerful skies,

in this the task and mighty labor lies.

- Virgil (70 BC - 19 BC)
Aeneid; Book VI, Lines 192-195, 29 BC - 19 BC