How Long is the Colorado River?

© Roschetzky Photography/

Written by Cindy Rasmussen

Updated: July 20, 2023

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Infographic about the Colorado River.
The Colorado River runs through seven states and carved the Grand Canyon.

The Colorado River is most famous for carving the Grand Canyon in Arizona. It starts in Colorado and flows all the way down to the Gulf of California. The river passes through seven different states and is part of the border between Arizona and Mexico. Just how long in the Colorado River? Is it the longest river in the US? Let’s find out.

Where is the Colorado River?

Grand Canyon National Park - Rafting

The Colorado River runs from Colorado down to the Gulf of California.

©Jim Mallouk/

The Colorado River is in the southwest US and twists through Colorado, across to Utah, down through Arizona, creating the border between Arizona and Nevada then down through California. It is the natural border between the US and Mexico for 24 miles, then heads south through Mexico to the Gulf of California. Other states in the Colorado River Basin include Wyoming and New Mexico. These states have rivers that flow directly into the Colorado River.

How Long is the Colorado River?

The Colorado River is 1,450 miles long, about the distance from Chicago down to Key Largo, Florida.


The Colorado River is 1,450 miles long. For reference, that is a little further than the distance from Chicago to Miami. A drive from Chicago to Miami is 1,384 miles. A little further down to Key Largo in the Keys is 1, 443 miles, so about the same.

You can also read about the depth of the Colorado River.

Where does the Colorado River begin?

The Colorado River begins in a small trout lake in the Rocky Mountains. La Poudre Pass Lake is the headwaters of the Colorado River. It is in the Rocky Mountain National Park and is accessible by a short trail. Rocky Mountain National Park itself is a huge tourist destination, with 4,670,054 visitors in 2019 alone.

Where does it end?

The Colorado River empties into the Gulf of California, ending just before the Gulf in the Sonoran Desert in Mexico.

Why is the Colorado River important?

The Colorado River is important because it provides:

  • domestic water supply for seven states, including Arizona, Nevada, California, Colorado, New Mexico, Utah, and Wyoming.
  • power for several hydropower plants along the river, including the Hoover Dam and the Glen Canyon Dam.
  • water for farmers and ranchers to irrigate their land and animals.
  • a runoff for smaller rivers and the snowmelt from the mountains.
  • a habitat for countless fish, waterfowl, and mammals.

What kind of animals live in and around the Colorado River?

Great Blue Heron catching a huge fish.

Great blue heron

lives along the Colorado River.

©David Byron Keener/

The river runs through deserts, canyons, mountains, and valleys. The Colorado River Nature Center and Wildlife Area is a 500-acre park along the river in Bullhead City, Arizona. As an example of the wildlife that can be found along the river, this park mentions the following animals:

What kind of fish are in the Colorado River?

What Do Trout Eat - Rainbow Trout Bursting from Surface

Rainbow trout and striped bass are two of the most common fish in the Colorado River.


There are a variety of fish in the river, including the two most commonly fished, striped bass and rainbow trout. You can also find some good-sized channel catfish. Other parts of the river will have plenty of smallmouth and largemouth bass, suckers, sunfish, and common carp.

How many dams are on the Colorado River?

There are fifteen dams along the Colorado River. Many lakes are formed above the dams along the river, like Lake Mead above the Hoover Dam and Lake Powell above the Glen Canyon Dam.

Is it the Longest River in the US?

No, the Colorado River is not the longest river in the US; it is the sixth-longest river.

What is the Longest River in the World?

The Nile is the longest river in the world.

©Feroze Edassery/

The longest river in the world is the Nile River in Africa. The Nile River is 4,130 miles long and interestingly flows north! It starts in Uganda and continues north to empty into the Mediterranean Sea.

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About the Author

I'm a Wildlife Conservation Author and Journalist, raising awareness about conservation by teaching others about the amazing animals we share the planet with. I graduated from the University of Minnesota-Morris with a degree in Elementary Education and I am a former teacher. When I am not writing I love going to my kids' soccer games, watching movies, taking on DIY projects and running with our giant Labradoodle "Tango".

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