The Divide

The Divide is a violent land torn apart by quakes and skin-flaying windstorms to the northwest of the Mojave.

Background
Before the War the land now known as the Divide was home to Hopeville and Ashton: a missile base and a city under its protection. Apart from being a major element of the balistic defense matrix, Hopeville was also the subject of a major Big MT research project concerning meteorology; a project that apparently ended in a disaster, spawning the horrible dust storms the Divide is infamous for. Beside the project, Big MT was also a partner in different enterprises: at one point, the entire local hippie commune that protested outside Hopeville against the ongoing Sino-American War were rounded up and shipped off to the Big MT Research Facility as test subjects.

The Great War apparently surprised the soldiers here, as the ICBMs never left their missile silos. It is possible that the aforementioned backfiring meteorological experiment has resulted in the soldiers here dying or fleeing before the American missiles could take flight. A silence fell across the land. For two centuries the soil of the Divide lay undisturbed by human presence. However, eventually, a small survivalist community estabilished itself in the area. Kept alive by couriers and traders, it prospered. It prospered enough, in fact, to draw the attention of the New California Republic, who annexed it swiftly and estabilished a supply line across the treacherous Divide.

This drew the attention of the Legion, which, in its bid to take the Mojave, attempted to cut the supply line with a sizeable force of legionaries striking against Republic's forces located here. But this war did not destroy the settlement. It was the work of a single Courier, who unknowingly delivered an Enclave detonator to the Divide a short time before the Bear and the Bull jumped to each other's throat. When this device was activated by the inhabitants, it sent a signal to the dormant nuclear giants lying in the silos beneath ground. They began detonating one after another, beneath ground, causing massive earthquakes, cracking and twisting the landscape. Entire companies of NCR soldiers in the Divide were trapped together with their Legion foes. The disaster created the Divide as it exists now: a wind-beaten maze of twisting canyons, skin-flaying dust storms and horrific abominations.

The Divide twisted the surviving NCR and Legion. As the winds flayed their skin and radiation ghoulified them, they became the marked men: skinless horrors fueled by hatred and rage for everything around them. Outside the Divide, the disaster became a blessing in disguise for the Legion: cutting off NCR supply lines along Death Valley Road and the Carson Pass Highway it granted Caesar's Legion time to recover after their loss in the First Battle of Hoover Dam. However, it also gave birth to the greatest, yet least known danger to the post-War civilization of the American Southwest: Ulysses. The Divide disaster both traumatized and inspired him as he learned the impact a single person, the Courier, can have on history.

Ulysses was determined to destroy both the NCR and the Legion by unleashing nuclear fire from the Divide upon their lands. NCR was guilty of spreading corruption and sickness across the wastes under the guise of "civilisation", while his former master's creation, the Legion, was responsible for the annihilation of Twisted Hairs, Ulysses' mother tribe. He walked the Divide many times and by 2281, was finally able to find a way to activate the missile silos laying inside the wind-ravaged canyons. But to complete this task, he needed the Courier to deliver him the final piece of the puzzle: a perfect copy of ED-E.

The Courier answered the call and confronted Ulysses at the Divide. There, under the Old World flag, the two decided the fate of the world.

Layout
Contains undetonated warheads, most likely nuclear warheads within ICBMs (Intercontinental Ballistic Missiles), which would be safe in an isolated location which the area around Hopeville seems to be.

Appearances
The Divide is mentioned in Fallout: New Vegas, and all its add-ons (Dead Money, Honest Hearts, and Old World Blues) and its map is shown in Old World Blues. It appears in the add-on Lonesome Road.

Behind the scenes

 * In Fallout Tactics, the airship expedition of the Brotherhood of Steel is damaged crossing a "great divide", causing them to crash near Chicago and eventually create the Midwestern Brotherhood of Steel. This is not the same divide since the divide is formed shortly before the time of Fallout New Vegas and Fallout Tactics takes place way before the time the divide was formed.
 * Before the release of Lonesome Road, Chris Avellone's Twitter avatar showed the Divide.