My husband and I took a short weekend trip to Yellowstone and took this time to get geocaches in three new states at the same time. On the drive up from Jackson Hole, our first two stops were in Idaho. The first one was particularly neat: Island Park Village Resort. The location was pretty obvious when we got near, and lots of goodies inside. We also stopped for a break and found this cache (Sticker Cache) in a muggle-heavy zone.
We then found a few in Montana, starting with Roadside TB Hotel. Welcome! This one wasn't too hard to find, even though there were muggles nearby. We followed it up with Welcome to West Yellowstone 1 again - my location seemed a bit off on this one, so it took longer than I suspect it should have.
We spent so much of our time exploring Yellowstone, we almost missed getting a cache in Wyoming. But we did manage to find Elk Refugee Viewpoint Version 2. We also explored a nearby museum (which was closed) and posed with the statues in the parking lot.