The nearest sizable city to Pullman is Spokane, about ninety minutes north via Colfax (the Whitman County seat and a notorious speed trap: take the speed limit signs seriously). Highway 195 bypasses all the other little towns on the way north, and there's only one gas station beside the highway between Colfax and Spokane, in Steptoe, so check your gauge before you leave town.
Mostly you'll see wave after wave of rolling Palouse hills. There's a rest stop on the west side of the highway about halfway there. And look for two charming railroad bridges together on the same side of the road as you move further north.
Passing can be hazardous on this winding highway except where there are a few passing lanes, but just after the turnoff to Spangle 195 becomes a divided four-lane highway. If you're stuck behind a slow-moving vehicle and see the huge dome of the IPGA (Inland Empire Pea and Grain) storage facility in the distance ahead on the right, be patient; the divided highway will start in just a minute.