In my first Athabaska Falls post I alluded to how deep the falls fell. The churning water has carved through these many layers of rock over centuries.
A little way downriver from where the falls drops now, is evidence of its previous course through the surrounding rock. The Parks Canada people have even inserted stairs so you can get a feel for the narrow gorge through which the water has passed.
This last photo is of where the water emerges to flow more sedately north after it has dropped over the falls and through the gorge.