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United States Penitentiary Tibbets, nicknamed the "Big Top" due to its distinctive rotunda dome, is a cold, sterile, steel-walled automated prison facility in what used to be known as Arizona, constructed before the Great War. It was designed to hold and protect some of the world's most dangerous criminals before the war. The facility is governed by the split-personality machine intelligence within the prison, ODYSSEUS (ULYSSES).


Tibbets was always a military prison, holding some of the United States' most dangerous criminals. Over time, the prison became more advanced, utilizing robotic wardens and utility robots to maintain the structure, especially as the war with China in the 2070s and the annexation of Canada began to drain personnel from the United States. It was designed to hold 636 prisoners at full capacity. The prison would be reprogrammed to serve as a quarantine prison, capturing those infected with New Plague, which it would continue to carry out after the bombs fell. When a new outbreak of the virus cropped up, the prisons' robotic wardens fulfilled their programming. By 2253, Tibbets was far beyond capacity. A catastrophic attack at the prison released the infected prisoners, posing a serious threat to the wasteland.

705th Military Battalion Van Buren

The logo of the military battalion that guarded the Facility

In 2040, Tibbets was commandeered by the United States government in association with Vault-Tec and Poseidon Energy to tie into their Safehouse Project. The prison was used for primitive isolation studies before the vaults were established, except the subjects were prisoners, especially conditioned to see if they could withstand the rigors of isolation for protracted periods of time. It was here where the recycling systems and water purification systems were tested before their implementation in Project Safehouse. Prisoners harmed during the procedure were humanely tended to.


Before the Great War[]

The United States Penitentiary (USP), Tibbets was located on 1,583 square acres, 22.8 inside the penitentiary walls. It was an all-male high-security level facility committed to carrying out the judgments of the Federal Courts. Tibbets provided a safe, secure, and humane environment for those offenders committed to its custody. Like all Bureau facilities, Tibbets adhered to a balanced philosophy that recognized that punishment, deterrence, and incapacitation are all valid purposes of confinement. Opportunities for positive change were provided through work, education, training, and counseling for inmates motivated toward self-improvement.

The USP Tibbets came into existence through an act of Congress in 1895. Inmates from the military prison at Fort Tibbets were used in the early construction and were marched 3 and a half miles to the site daily, returning to the prison at the Fort at night. This continued until February 1903 when the first 418 inmates to occupy the prison site were moved into what would later become the laundry building. Prisoners and supplies for the prison were handled via a rail line that passed through the prison to unload and load cargo.

In 1906, all federal prisoners from Fort Tibbets were housed in the new institution and the prison at Fort Tibbets was returned to the War Department. A milestone in the new penitentiaries' construction was reached in 1926 with the final placement of the dome overhead the rotunda - from which the penitentiary derives its famous nickname - "The Big Top."

On April 5, 2040, the Secretary of the Army made the decision to build a new Disciplinary Barracks, with a capacity for 456 inmates. A cost ceiling of $363 million in allocated construction dollars was set. The target budget year for funding this project was the fiscal year 2041. Construction began in the Fall of 2042, with completion projected for the fall of 2045.

In July 2042, discussions began with Vault-Tec to determine space and functional requirements for the new facility. On 6 September 2042, the Combined Arms Center Commander was given a decision brief of the disciplinary barracks project and selected one of three design options for further development. He also requested the Corps of Engineers to research an alternate location for the placement of this facility, since the geological evaluation of the site adjacent to the Trustee Unit revealed unsuitable subsurface conditions. Discussions involving the possible movement of the prison and relocation projects were also discussed, leading to the three-rail system that would come.

The planning process reached the 10 percent stage on 4 Oct 2042; the 35 percent stage on 27 March 2043; 65 percent stage on 19 January 2044; 90 percent stage on 3 May 2045; and 100 percent stage on 15 August 2046. The 100 percent Design Meeting was conducted on 16 October 2046.

During the Resource Wars, Tibbets housed war criminals and deserters from the Yangtze Campaign. After the events of the Hoover Sabotage and the release of the Limit-115 samples in Denver, Tibbets became a quartine prison, programmed to capture anyone who had been infected. Even though ODYSSEUS was retrofitted for maintaining the prison and monitoring the prisoners, he still retained an inordinate amount of security clearance. Other than prisoners, no humans were present at Tibbets. ODYSSEUS commanded the all-robot staff, including the seldom-roused ARGOS, who served as the tireless defender of the prison. The government wanted ODYSSEUS to be able to "advise" on the spread of plague vectors in the case of a prison break. This included warming up launch sites like B.O.M.B.-001.

After the Great War[]

Victor Presper and his followers released the New Plague virus in the remote areas near Boulder and Denver. It was close enough to the quarantine prison to spur ODYSSEUS into action, but not near enough to huge populations to start a general panic. Due to its pre-War programming, ODYSSEUS would track and arrest all infected people. ODYSSEUS was far too secure for Presper to hack, so the only way he could get the artificial intelligence to send the launch codes to the B.O.M.B. was to lead ODYSSEUS to calculate that too much of the region had been infected for conventional containment. In order to achieve that, Presper's men would attack the prison, allowing everyone to escape. This event would start a countdown for the missile launches from B.O.M.B.-001. ODYSSEUS would assess the viral spread, try to gather up the escaped prisoners, and once 90% of the prisoners had been retrieved, launch nuclear missiles to kill any other carriers and prevent any further spread.

ODYSSEUS' plan is to continue to send out robots after the prisoners until they all have been brought back to the prison. The eye-bots and ARGOS rounded up most of the escapees pretty quickly - other than the Prisoner and six others (Blackjack, Daniel, Chagas, Mallet McBride, Ginger Flowers, and Jillian McKinley). ODYSSEUS seems unconcerned with prisoners that stream back out again after being captured.

The presumption of the Prisoner was that once all of the prisoners returned, ODYSSEUS would just settle down and leave everyone alone. However, after all of the prisoners were returned it did some massive calculations of where everyone had traveled and showed that the prisoners have spread the Limit-115 to a variety of places. At that point, ODYSSEUS made the determination that the plague was spreading too far, and so armed the B.O.M.B. satellite and melted itself down to try killing all of the prisoners.


Tibbets offers a wide range of education programs from basic literacy to high school equivalency (GED) to parenting programs through the Personal Information Processor issued to each inmate. The Bureau utilizes the high school equivalency as its literacy standard and inmates failing to meet this standard are required to participate in education programs. In addition, the Education Department offers English as a Second Language and bi-lingual Adult Basic and Secondary Education opportunity.


The Vault-Tec operation at Tibbets is the largest in the Bureau and includes three factories. These factories employ over 320 inmates and last year recorded sales of over 26 million dollars with profits exceeding 6 million dollars. The profits from all Vault-Tec operations are used to fund salaries, re-invest in new factories, and other expenses of Vault-Tec.

Health Services[]

Health Services provides a full range of outpatient and infirmary care to all inmates. There are 26 full-time medical staff members, including two physicians, two dentists, two pharmacists, nine physician assistants, two health information personnel, an administrator, and an assistant administrator. The automated medical staff includes six Auto-Doc systems and a number of on-call medical robots. This staff provides 24-hour coverage and specialty services are provided by consultants from the community. Four hospitals in the local area offer inpatient and outpatient care on a contractual basis.


USP Tibbets provides a residential treatment program to those inmates interested in making pro-social life decisions and uses the latest in psychological methods and technology. The Challenge, Opportunity, Discipline, and Ethics (CODE) program is a year-long residential treatment program offered in the prison. The mission of the program is to foster a sense of trust, responsibility, integrity, and tolerance. Inmates enrolled in the program spend the first three months exploring the change process, followed by six months of daily treatment methods to promote positive life skills, and during the final three months of the program, inmates develop skills to discourage relapse into prior negative forms of thinking, feeling, and behaving.


Tibbets is self-sufficient. It has a recycling water supply, a waste recycling system that extracts moisture from human waste, and it has several stockpiles of oil, petrol, fusion cells, and electrical batteries to keep it going for at least fifty more years. It has exploited its massive stockpile in ties with Robot City to "beef up" in preparation for its escape.

Relationship with other communities[]

Tibbets has no relationship with any other communities in the Wasteland west of its location - most of them don't know it's even there. The only "communities" that know of its existence are the machine intelligence governing Robot City to the East, which are attempting to find ULYSSES and correct the "divide" that has occurred within its system - and return it to its imprisoned, intended place as their slave.[1]


Tibbets Prison was originally referred to as Big MT in some design documents, a name that would later be reused for the Big MT Research Facility in the Fallout: New Vegas add-on Old World Blues.[2]


The Tibbets Facility was to be the starting location in Van Buren, the canceled Fallout 3 by Black Isle Studios.

Behind the scenes[]

Tibbets Prison is named after Paul Tibbets, the pilot who flew the Enola Gay B-29 Superfortress that dropped the Little Boy nuclear bomb on Hiroshima.