When you think about Yellowstone National Park in Wyoming, you probably think of the geysers and hot springs, but there is more to see there. Grand Canyon of the Yellowstone is an impressive canyon that was carved by the yellowstone river. It has two large waterfalls on it, the first is called Yellowstone upper falls.
I've been to Yellowstone twice, the first picture I took on my 2010 trip and the rest are from my 2019 trip.
There are a few places you can get a view of the upper falls. This is probably the best place to view the falls in context, you can see the bridge above the falls, and the top of falls overlook.
Another good place to see it is from the Canyon overlook at Uncle Tom's Point. You are above the top of the falls looking down on it.
Also at Uncle Tom's point there is a narrow set of stairs that can take you lower so you are looking straight at the falls. They were closed when I was there so I don't have a picture from it
Finally, there is an overlook right at the top of the upper falls where you can stand and watch the water go over the lip of the falls from just feet away. Alas, that overlook was closed when I went there in 2019, they were doing major reconstruction of it, so hopefully in 2020 and beyond it will be open with stunning views.