It wasn't even noon yet as we were passing north out of Hayden Valley on our Yellowstone exploration. There was plenty more to see. The Yellowstone River pulled away from the road and out of view as both it and we came upon the 400-500 feet deep Grand Canyon of the Yellowstone.
Waterfalls can be found throughout the park; I'm not sure whether there are more geysers or waterfalls, but both abound. But the two biggest falls are near the beginning of this canyon, the Upper Falls and Lower Falls. There are observation points for both falls on both banks of the river. We opted to stop on the south side, at the head of Uncle Tom's Trail. Named for the man who first forged it (originally a series of rope ladders), it starts from a high vantage overlooking the Upper Falls...
...and takes about a mile to go three-quarters of the way down into the canyon for a breathtaking view of the Lower Falls.
Later, we also stopped at a good point on the north side of the river that afforded a most impressive view of the canyon itself.
Hard to believe that a lush, green valley lay just a few miles to the south, but that's Yellowstone for you. The terrain would transform yet again as we came as far north as the Grand Loop Road runs and began traveling west. Soon we were in a very hilly area, where we stopped for a look at a petrified tree.
I believe that Yellowstone has a whole petrified forest somewhere along its northeast entrance road. My one regret of the trip was that we didn't do a little more investigation into that. But the guide book we were working from indicated it was along one of Yellowstone's most "grueling" hikes, and at this point in time, we figured that was something we might come back to the next day. (We didn't fully appreciate just how tired we'd be after this especially full day.) So instead we opted for the "hike free, one tree only" version of the petrified forest, a solitary stone tree that stands elsewhere in the park, along a short side road.
You can't get any closer to it than this; it's surrounded completely by fencing (as you can see in the background). Still pretty neat, though.
We stopped at another waterfall a few miles west, the Undine Falls. In a more forested area than the two grand waterfalls we'd seen earlier, we decided it was a nice spot to dip into our food stuffs and have lunch, a picnic/tailgater in the back of the truck.
Our next stop would be Mammoth Hot Springs.