sdi

Then thus replied the prophetess divine:
"O goddess-born of great Anchises' line,
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 labour lies.
To few great Jupiter imparts this grace,
And those of shining worth and heav'nly race.
Betwixt those regions and our upper light,
Deep forests and impenetrable night
Possess the middle space: th' infernal bounds
Cocytus, with his sable waves, surrounds."

(Virgil, Æneid VI, as translated by John Dryden)

Rich indeed is he who can keep his gates open day and night! (But riches of what kind?)