Whose woods these are I think I know.
His house is in the village, though;
He will not see me stopping here
To watch his woods fill up with snow.

My little horse must think it queer
To stop without a farmhouse near
Between the woods and frozen lake
The darkest evening of the year.

He gives his harness bells a shake
To ask if there is some mistake.
The only other sound's the sweep
Of easy wind and downy flake.

The woods are lovely, dark, and deep,
But I have promises to keep,
And miles to go before I sleep,
And miles to go before I sleep.

---

In my view, this is Frost's best poem and one of the greatest one-paged poems in the English language. It is technically flawless; I cannot add or subtract a single word without harming the poem. Perhaps many scholars have overanalyzed it, reading too much into it. As far as I can see, there are two legitimate interpretations. One is that a man stops to rest by snowy woods, where it is profoundly and stirringly quiet. It's the 'darkest evening of the year' - which here can be taken literally. 'The woods are lovely, dark and deep' simply means what is says - namely, that they are dark and deep (you can see it, can't you?) , and that the speaker is stirred by the magical scenery. But the speaker can't stay for as long as he'd like, for he has pressing responsibilities.

A second interpretation hinges on 'The woods are lovely, dark and deep'. Rather than the line simply describing a beautiful scene, it also suggests a contemplation of suicide.