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Grand Canyon
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The Grand Canyon at night by Joe Sanabria
FactionsCaesar's Legion
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The Grand Canyon, sometimes referred to as Magnum Chasma ("Great Abyss") by members of Caesar's Legion[1], is a steep-sided canyon carved by the Colorado River in the United States in the state of Arizona.


Gray paragraphs are based on Van Buren and were not confirmed by primary sources The demand for uranium before the Great War motivated the U.S. government to revoke the Grand Canyon's national park status. Private mining companies were permitted to excavate uranium ore in the Canyon, resulting in an environmental disaster. Widespread contamination and presence of irradiated byproducts of the mining process resulted in it becoming one of the deadliest places in the wastes, populated by hideous mutants indigenous to the area.

Above the devastation rose (and continues to do) a sky tram connecting the opposite cliffs. This miracle of pre-War engineering did not age well, however, as much of its mechanisms were scavenged over the decades. Recovering the unique, irreplaceable elements would allow a wastelander with a knack for repair to restore the tram to full functionality.

Just prior to the Great War, Fredrick Sinclair would choose a site close to the Grand Canyon to construct the Sierra Madre an entirely self-sufficient casino and resort largely away from civilization.

When the Great War took place, the Canyon was spared much of the devastation. In time, it became home to many Tribes, such as the Blackfoot and several others. These tribes were largely isolated from other larger groups and people, and soon developed their own dialects and also regularly fought amongst each other. While the Grand Canyon tribes weren't bothered by outsiders much, the Followers of the Apocalypse were interested in the dialects that the Grand Canyon tribes had developed and sent a small expedition, consisting of Edward Sallow, an anthropologist and linguist,[2] Joshua Graham, a Mormon tribal specialist picked up from Utah, Bill Calhoun, a physician, and nine others, to meet with the tribes and learn the languages of the local tribes. The group was captured by the Blackfoots for an unknown reason (Caesar suspected a ransom, Graham believes it was a mistranslation) while they were fighting with all seven other tribes of the Grand Canyon. Unwilling to die with the Blackfoots, Sallow, against the advisement of his group, taught the Blackfoots how to maintain their equipment, make explosives and wage total war. With Sallow's help, who later took the name Caesar, the Blackfoots would either destroy or assimilate all other Grand Canyon tribes and would later give rise to Caesar's Legion.

In 2277, Legate Joshua Graham, was covered in pitch, set alight and thrown into the canyon by Caesar, due to his failure to capture Hoover Dam during the First Battle of Hoover Dam, and the severe casualties sustained among the Legion forces during the battle. Graham would survive the fire and plunge into the canyon and gave rise to the legend of the Burned Man.



The Grand Canyon did not appear in any of the published games, but was to appear in the cancelled Fallout 3 project by Black Isle. The player was supposed to enter the canyon to locate the remains of the second B.O.M.B. orbital station. On the way, he'd encounter a handful of characters, including scavengers and Victor Presper's soldiers.

It was mentioned in Fallout 2 by Harold,[3] and in Fallout: New Vegas, and is shown via intro slide shows in the Fallout: New Vegas add-ons Dead Money and Honest Hearts.




  1. The phrase "MAGNVM CHASMA" is used in reference to the Grand Canyon in the inscription on the back of Legion denarii.
  2. The Courier: "What changed you from a Follower to dictator?"
    Caesar: "When I was 20, the Followers sent me East to Grand Canyon. It was my first expedition, just me and a physician named Calhoun. As an anthropologist and linguist, my assignment was to learn the dialects of the Grand Canyon tribes. What a fucking waste of time!"
    (Caesar's dialogue)
  3. The Chosen One: "{122}{}{This place is coming apart?}"
    Harold: "{127}{hld4a}{Well, sorta. Our atomic reactor’s a mite...sensitive. The people I got running it mean well, but... well, they are not the sharpest tools in the shed. If you know what I mean.}"
    The Chosen One: "{130}{}{What do you mean?}"
    Harold: "{138}{hld6}{Need a little time on the whetstone yourself, huh? I mean they are not too bright. Here’s an example. The other day I get a report. On it, it says the main coolant valve should be shut down. That woulda caused a meltdown that would make the Grand Canyon look like a pig wallow.}"