Fifty-four miles north of Walla Walla and 83 miles west of Pullman, off Hwy 261, this jaw-droppingly magnificent waterfall tumbles 198ft down a craggy, dry valley. If this were closer to a major city the roads would be clogged with tour buses, but for now its only claim to fame is that it became Washington's official waterfall in 2014. Is it worth the drive? A thousand times yes. A Discover Pass is required for park entry.
You can do a (very poorly marked and vertiginous) loop hike from the ridge to the top of the falls and down into the gorge in about 1½ hours, but pay attention to the warning signs posted everywhere: people die here each year when they stray too close to the edge. There's also a small campground with 11 primitive tent sites (no RVs; sites $12).