On a rainy January day in Seattle, the speaker looks out at soaked yards and starts to wonder something small and oddly practical: how do moles stay dry, or at least avoid drowning, when the ground is so waterlogged? The question grows into a kind of admiration. Moles ignore our property lines, which mean nothing in their world of "claw and tail," and even at a glittering city overlook, their mounds dot the lawn.
The speaker begins to see these hills as a celebration, with the "slim, blind chiselers" below the grass as the real guests of honor. By the end, the tone is warm and a little playful. Instead of resenting the damage to the lawn, "we" think about scattering wildflower or clover seed over the new bumpy ground. The mood is calm and curious, like the walk in the title, and it ends in gladness and awe at the "soft, tiny engineers" who keep going through the storm.