My Captain does not answer, his lips are pale and still;

My father does not feel my arm, he has no pulse nor will;

The ship is anchor'd safe and sound, its voyage closed and done;

From fearful trip, the victor ship, comes in with object won;

Exult, O shores, and ring, O bells!

But I, with mournful tread,

Walk the deck my Captain lies,

Fallen cold and dead.

—"O Captain! My Captain!"
Walt Whitman

In this final stanza, what does the speaker mean with the phrase “its voyage closed and done”?

The ship will not be taking any more voyages
The army has won the war.
The army has stopped fighting in the war.
The ship is no longer accepting passengers.