Grand Canyon of the Yellowstone - Yellowstone National Park

The Grand Canyon of the Yellowstone is the primary geologic feature in the Canyon District of Yellowstone National Park. It is roughly 20 miles long, measured from the Upper Falls to the Tower Fall area. The canyon is up to 900 feet deep and a half mile in width.

The colors in the canyon are also a result of different iron compounds. When the old geyser basin was active, the "cooking" of the rock caused chemical alterations in these iron compounds. Exposure to the elements caused the rocks to change colors. The rocks are oxidizing or rusting. The colors indicate the presence or absence of water in the individual iron compounds. Most of the yellows in the canyon are the result of iron present in the rock rather than sulfur.


The falls are erosional features formed by the Yellowstone River as it flows over progressively softer, less resistant rock. The Upper Falls is upstream of the Lower Falls and is 109 ft. high. It can be seen from the Brink of the Upper Falls Trail and from Uncle Tom's Trail.

Pictures ENLARGE if you click on them.

Pictures ENLARGE if you click on them.

A third falls can be found in the canyon between the Upper and Lower falls. Crystal Falls is the outfall of Cascade Creek into the canyon. It can be seen from the South Rim Trail just east of the Uncle Tom's area.

The Lower Falls is 308 ft. high and can be seen from Lookout Point, Red Rock Point, Artist Point, Brink of the Lower Falls Trail, and from various points on the South Rim Trail. The Lower Falls is often described as being more than twice the size of Niagara, although this only refers to its height and not the volume of water flowing over it. The volume of water flowing over the falls can vary from 63,500 gal/sec at peak runoff to 5,000 gal/sec in the fall.

Pictures ENLARGE if you click on them.

The Yellowstone River is the force that created the canyon and the falls. It begins on the slopes of Yount Peak, south of the park, and travels more than 600 miles to its terminus in North Dakota where it empties into the Missouri River. It is the longest undammed river in the continental United States.