What national park is in Arizona? The Colorado River runs through it. It covers over one million acres of land. It is 277 miles long. It gets about five million visitors a year. It is Grand Canyon National Park.
The Grand Canyon was not always a national park. Native Americans lived there. Later the canyon was used for mining. Then, people started to visit. Some wanted to study the rocks. Some wanted to study the animals. Some wanted to hike the land.
In 1869, Major John Wesley Powell started down the Colorado River. He took nine men with him. They had four boats. They were the first group to explore the canyon by river. Until then, many people had not heard of the Grand Canyon.