As the Colorado River ran through, it slowly eroded the rock away until it got as big as it is today. Technically speaking, the Grand Canyon is still growing thanks to this process.

Rocks gathered along the Colorado River contained evidence of a bustling community of animals in an ancient sea.

The collision of a meteorite in what is now Arizona left an indelible mark: Meteor Crater. At nearly the same time, a massive landslide blocked the Colorado River, creating a temporary lake in ...

The Grand Canyon’s North Rim has been special to generations of Americans. A frequent visitor reflects on this national park’s less busy side and what wildfire has taken away.

Bigger than Rhode Island The Colorado River cuts through Grand Canyon National Park for about 278 miles (447 kilometers), pushing across northwestern Arizona. The eastern boundary is near the ...

It’s time celebrate the adventure life of the professional women guides who run the famed stretch of whitewater that flows through the Grand Canyon ...

Hells Canyon, the deepest river gorge in the United States, was carved just about 2.1 million years ago — making it much younger than the Grand Canyon.