The Grand Canyon of the Yellowstone is the primary geologic feature in the Canyon District.
It is roughly 20 miles long, measured from the Upper Falls to the Tower Fall area.
Depth is 800 to 1,200 ft.; width is 1,500 to 4,000 ft.
The canyon as we know it today is a very recent geologic feature.
The present canyon is no more than 10,000 to 14,000 years old, although there has probably been a canyon in this location for a much longer period.
The exact sequence of events in the formation of the canyon is not well understood, as there has been little field work done in the area.
The few studies that are available are thought to be inaccurate.
The canyon is known to be formed by erosion rather than by glaciation.