River Drive 
Please join us in our drive on the other side of the Yellowstone River. 

About 15 minutes later by car, we came to Tower Falls pictured right and above. A sign explained that the path below would not take us to a place where we could view the lower falls, but we took it anyway. It was downhill.
They were right -- no entry toward the bottom of the falls.
I got closer -- with Elaine tugging on my jacket not to go further.
But isn't that rainbow the spray of the bottom of the falls?
It took us 43 minutes to drive from the top end of that dotted line to the "YOU ARE HERE" sign, and were greeted by this fantastic view of the Yellowstone River, above and below.
The cliff across the canyon has strata and layers explained here.
And below is that staircase we saw from the other side.
But we got some pretty views of the river from down here.
But I tried my best to get a view of the falls -- climbing over this barricade. 
Best I could do -- there really was no way to see the bottom of the waterfall.
Next, we finish the day with more Mammoth Springs -- the Upper Terrace Drive.