
Its Geologic Formations
Geologic formations are a common theme in Colorado. As always, they remind us of her diverse pre-historic past. Also, almost every location in the state inspires us with visual reminders of it. Furthermore, Colorado’s many inspiring and scientifically fascinating sites spark a barrage of what, when, how, why, and who questions. Colorado National Monument is no exception.
As a teacher, I love the “outdoor classroom” that is Colorado. Too, it’s a great opportunity to discover, learn and teach our children about geology, geography, nature, astronomy, history, and culture. Without a doubt, you will find that Colorado National Monument is a great place to do that. It is a cornucopia of sandstone formations located between Fruita and Grand Junction. While there, you should explore it further by taking Rim Rock Drive. And along this route, you will be able to stop at 19 scenic overlooks and hiking trails. While here, it’s a perfect place to scope out rock formations created by wind, water, and geologic activity. As well, below is a list of the geologic development of this area from oldest to newest.
The Geologic Timeline of Colorado National Monument

- Precambrian 1.7-1.5 billion years ago. Called Basement rocks, they are composed of gneiss, schist, and granites.
- Upper Triassic Chinle Formation 210 million years old and is an 88 ft thick, red mudstone, shale & limestone conglomerate.
- The Lower Jurassic consisting of Wingate Sandstone is 200 million years old and 329 feet thick. It is comprised of eolian sandstone.
- Lower Jurassic and the Kayenta Formation is a 190 million-year-old, 76-foot thick sandstone, and shale conglomerate.
- Middle Jurassic Entrada Formation is 165 million years old. A-Boards Beds Member and Slick Rock Member. It is a 151 foot thick, Salmon-colored eolian (wind-deposited sandstone with a white bedded unit on top).
- The Middle Jurassic Wanakah Formation is 160 million years old. It is 31 feet thick and composed of thin red mudstone, sandstone, and green shale.
- Upper Jurassic Morrison Formation is a 150 million-year-old Brushy Basin Member. It is 305 feet thick, red, green, purple, gray mudstone and bentonite, and some sandstone. As well, it’s a Salt Wash Member 93 feet thick with thick channel sandstone and minor red to green floodplain mudstone. A Tidwell Member is 143 feet thick with interbedded sandstone and green mudstone, and thin limestone lenses.
- Lower Cretaceous Burro Canyon Formation is 140 million years old and 100 feet thick. Itis comprised of sandstone, conglomerate, and green mudstone.

Colorado National Monument’s More Recent History
John Otto
In 1906, a man named John Otto saw these rugged, red-rock canyons south of Grand Junction for the first time. What is more, he was so inspired by their beauty he fell in love with them. Also, he began a one-person effort toward National recognition of these beautiful canyons and inspiring rock formations. As a result, he wrote editorials and regularly sent letters to Washington politicians to gain their support.
During this time, John Otto lived in the canyon. And in addition to his written efforts, he built its extensive trail system using only a pick and shovel. Fourteen trails now cover over 40 miles. Today these trails will take you to some well-known sights in Colorado National Monument.
Otto was a patriot. Because of this, he named the rock formations after heroes and historical events. Furthermore, some of the formations, such as “Independence Monument” and “Liberty Cap,” still bear these names. While other formations took on names inspired by their shapes, such as “Pipe Organ” and “Widow Rock.” In the end, through his tireless efforts, Colorado National Monument was recognized, honored, and made accessible to the public.
Hiking Trails at the Monument
- Devil’s Kitchen- easy
- Liberty Cap- moderate
- Ute Canyon- moderate
- Coke Ovens-easy
- No Thoroughfare Canyon-moderate
More hiking trails in the Grand Junction area
Hiking trails by the National Park Service
This 20,500-acre maze of canyons and rock spires is a great place to visit and hike during the day. As well, you should also venture to see it at night to view the brilliant star and planet studded skies.
