The Grand Canyon of the Yellowstone is one of the breathtaking sights inside Yellowstone Park. Nearly 40 km long, the canyon is up to 1200 meter wide and 400 meters deep in places. From several vantage points, you can view Lower Falls and Upper falls plunging into the canyon.
The Yellowstone is the last free flowing river in the lower 48 states. From its headwaters in Lake Yellowstone downstream 1200 km to the Missouri River in North Dakota. The Yellowstone River flows as it has for centuries, in its natural state, undammed and untamed carving the canyon in the past centuries.
The colors in the Grand Canyon of the Yellowstone are created by mineral stains marking the locations of hot springs and steam vents in the canyon walls. For thousands of years, upwardly percolating fluids have altered the chemistry of the rocks, turning them yellow, red, white, and pink.
When the old geyser basin was active, the “cooking” of the rock caused chemical alterations in the canyon’s iron compounds. The rocks are essentially 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, as many people think.
The present day canyon was formed between 10,000 and 14,000 years ago and a variety of geological forces continue to shape the canyon today, including; earthquakes, erosion, water and wind.