Grand Canyon Guide

Almost two billion years of planet Earth's geological history can be seen at this natural wonder of the world...

How the Mighty Grand Canyon Formed

Explosive Prehistoric Volcanic Eruptions

Hot magma, flowing from the depths of the the crust built magnificent stratovolcanoes. Explosive volcanic eruptions submerged the region under ash, volcanic debris and lava flows. Deep underneath the volcanoes were pockets of molten rock (called magma chambers) that supplied the volcanoes above. As new chambers and volcanoes formed, older magma chambers cooled to form solid igneous rock masses called plutons.

The development of what is today known as Lake Mead and Grand Canyon began as weakened, stretched crust fractured and faulted. Huge blocks of crust slid down along faults, creating abysmal basins which filled with sediment eroded from the neighboring uplifted blocks almost as fast as they subsided. Extensive lakes formed where water was trapped by the massive newly developed mountain ranges.

The Birth of The Colorado River

A Tiny Stream Steadily Erodes Northeastward Bit by Bit

Volcanic activity and faulting in the Lake Mead region continued until about 2 million years ago when another geologic event was about to begin that would forever change the Lake Mead landscape.

Approximately five million years ago the landscape was towered by elongate ridges that had shed thick fans of sediment into neighboring valleys. A small stream that flowed from the Lake Mead region into the Gulf of California had been steadily eroding northeastward bit by bit. Finally, it cut through the cliffs at what is now the mouth of the Grand Canyon near Pierce Ferry. This is the birth of the Colorado River as we know it today!

The First Inhabitants and Explorers

The Discovery of this Great Chasm

The first known inhabitants of the Grand Canyon arrived approximately 11,000 years ago and were known as the Paleo-Indians. Their Asian ancestors are thought to have crossed the Beringia land bridge beneath the Bering Strait and migrated to the continent of North America approximately 25,000 years earlier.

In 1540, Spaniard Francisco Vasquez de Coronado was searching for gold and the Seven Cities of Cibola when Indians told him of a great river to the north. Coronado and a party of 12 men were guided by Hopi Indians and 20 days later found themselves at the edge of a great chasm - the mighty Grand Canyon. After three frustrating days searching for a way down to the river Coronado and his men moved on, in search of other legends.

The Grand Canyon and all of its splendor was then left to its original inhabitants, the Indians, and remained so for over three more centuries until 1869, when a one-armed civil War veteran Major John Wesley Powell set out with four boats to explore the Colorado River. After losing two of this boats and three of his men. Powell eventually navigated the Colorado, reached the point where the Hualapai Indian Reservation and Lake Mead are today, 72 days later. Theodore Roosevelt exclaimed in 1903:"Absolutely unparalleled throughout the rest of the world... leave it as it is. You cannot improve upon it. The ages have been at work on it... what we can do is to keep it for children, your children's children, and those who come after you as one of the great sights which everyone should see."

Grand Canyon Quick Stats

Comprising Six of the Seven World-wide Climate Belts

The ancient mountain range which now rests at the bottom of the Grand Canyon was formed approximately 1.7 billion years ago. The Canyon itself took 3 to 6 million years to form. There are 70 species of mammals and 250 species of birds. The Grand Canyon comprises six of the seven world-wide climate belts ranging from the Mexican Desert to the Arctic-Alpine. The Canyon was formed by the Colorado River flowing west through the canyon at an average speed of 4 mi. (6.4 km) per hr.

Prehistoric Eruptions:

Explosive volcanic eruptions submerged the region under ash, volcanic debris and lava flows. Deep underneath the volcanoes were pockets of molten rock (called magma chambers) that supplied the volcanoes above.

Birth of The Colorado:

Approximately five million years ago the landscape was towered by elongate ridges that had shed thick fans of sediment into neighboring valleys. A small stream that flowed from the Lake Mead region into the Gulf of California had been steadily eroding northeastward bit by bit.

The First Inhabitants:

The first known inhabitants of the Grand Canyon arrived approximately 11,000 years ago. This is a typical Pai Indian camp scene during the Ghost Dance (circa 1870) years held near the Historic Grand Canyon Ranch.