Up ahead in the distance I spotted a small building, the small size and protruding vent pipe clearly marking it as a toilet. I had arrived, apparently. Let the outhouse show the way!  I drew closer and could now see some signage, well made and quite detailed. I was surprised at both the signs and facilities, given the remoteness of the place. How many people came to see this?  More than I thought, apparently.

The display thoughtfully provided shapes for each type of dino-print. Armed with these search images, I headed down towards the river, where the trackway was. The Purgatoire had exposed these trackways, washing away the layers of sedimentary rock that had accumulated since the Jurassic.

Hmm...was that one?  Three projections, the middle one longest...  It must be, that's gotta be an Allosaurus! I don't know why I thought these tracks would be as clean and sharp as a coon's paws in mud. The markings were indistinct and rough around the edges, but hey, they were mud turned to rock and so old I couldn't really wrap my mind around the concept of that much time.  The prints were also filled with mud from the last overflow of the river, which gave some of them a surreal, made-yesterday look.

Over there...a few round potholes - Brontosaurus! These tracks were perhaps the diameter of a telephone pole. Sitting in one of them was Texas Horned Lizard, cocking his head to watch me approach.  The irony of that moment was delicious. What terrible lizards the Age of Mammals can muster is a far cry from what walked here in bygone days. He skittered away but I scooped him up for a closer look and a picture or two.  I gave him his freedom and he scurried under a bush and looked at me some more.

The majority of the tracks were on the other side of the river, so I carefully made my way across. It wasn't very deep, but the rocks were slippery with moss and algae.  This would be a very bad place to break a leg. On this side of the river, much of a younger layer of strata remained; a hard layer perhaps six inches thick, which fractured and broke into large rectangular blocks as the thin, soft layer underneath it washed away.  It was this thin layer that had covered all of these prints, filling them in, and hardened to make fossils out of them. A layer of what - mud?  A sudden, heavy flood perhaps?  Volcanic ash? I had questions without any answers, but the rocks still had a story to tell me.  Once the hard, thick layer was exposed to the elements, and frost and flood cracked them into blocks and torrents washed them away, the softer, thinner layer went through the same process, and behold! Dino-tracks. Now the tracks were exposed and taking their turn under entropy's grindstone. Or rather, the rocks around the footprints - they are much like a teapot, which is nothing without the hole in the middle.

A hundred and fifty million years ago, dinosaurs walked along the shore of an ancient lake, their feet leaving depressions in the soft mud, which dried in the sun. Not very long after, some event occurred that resulted in the depressions getting filled with a softer material, which was lucky for us hominids happening on the scene much later. It's all a question of timing - had I visited a million years earlier, the prints might still be under layers of rock. Had I made the long hike into the canyon a million years from today, I may have been too late, the layer of prints having been washed away. In geologic terms, I was at the right place at the right time, give or take a couple eons.  A mere sliver of earth time, almost a snapshot, really. Fortunate happenstance and a complete mind-freak if you think about it too much.