Yellowstone National Park is an amazing place. I think you could spend a summer there and not see everything.
One of the things that surprised me was the amount of geothermal features, there must be thousands. It’s so impressive.
Here is a video and a few pics from our visit last summer.
This is in the Upper Geyser Basin
Don’t remember the name of this hot spring, but it’s pretty
Morning Glory Hot Spring
Mammoth Hot Springs Terraces