Here’s a couple of waterfalls in and around Yellowstone National Park.
Mesa Falls is located outside of Ashton, Idaho west of Yellowstone National Park. Located in a steep gorge, the falls drop about 140 over a shear cliff.
Osprey Falls are the Yellowstone Back Country, requiring a hike (or bike ride) to the top of a gorge. Then one must hike down into the gorge to see the falls, then back out. It’s not easy, but the falls are quite lovely and well worth the effort.