In just six short lines, the speaker pictures a journey that has suddenly run into something huge. The road is "plain and ready," which suggests a path that felt simple, maybe even confident, as if the traveler expected nothing to get in the way. Then the peak appears, standing "alone as a drowsy god."
That comparison is the heart of the poem. A god is powerful and awe-inspiring, but a drowsy one is not actively hostile. The mountain doesn't attack or threaten. It simply sits there, half-awake and indifferent, and its sheer size is enough to stop everything. The title, "Impediment," confirms this: the mountain is an obstacle, though a strangely quiet one.
The mood is hushed and a little humbling. The speaker seems small and perhaps uncertain, facing something that doesn't even need to try to matter. There's respect here, and maybe some frustration, but no panic. The poem leaves us at the moment of encounter, with the road ready and the mountain unmoved.