May in the mountains was a little cold but the prices were right. Yellowstone was just officially open for the season, and the rates at Old Faithful Inn were $16 a night. Campground was $12 a night. We stopped at all the pull outs and almost had the place to ourselves. On the way to Yellowstone we stopped at Craters of the Moon, Tetons, Burns, Bend, and Redwood National Park.