Fallout has always stood out as one of the most atmospheric and creative RPG franchises. With a myriad of changes or evolutions since the original Fallout for PC, one thing specifically had reigned intact; vaults. Vault-Tec may have offered refuge for some, but in doing so, had personal agendas.
Experiments galore, some front and center while others are more hidden in the background, nearly every vault proved to stem from something dark or morbid. While some installments are swimming in vaults, others only have a few. Fallout 76 may not have a ton, but the lore to back them up is present, and the game continues to grow.
It's worth noting that vault 63 will not be mentioned due to knowing little to nothing about it. It appears to be cut content from the now discontinued vault raids.
6 Vault 76
Vault 76 acts as your starting point in Fallout 76, so most players should be reasonably familiar with it. Deemed the "Official Vault of the Tricentennial," Vault 76 housed 88 in total and acted as one of 17 control vaults as part of the Appalachia Vault Experiment.
The experiment that vault 76 housed appeared to be one of mere diversity, but it focused more on the adverse effects solitary has on an individual. Inhabitants, or vault dwellers, were cataloged to have been successful before the great war and possess competitive traits. Thus, issues popped up often. But adversely, the overseer owned all the power over dictating solitary punishment, and security was equipped with non-lethals.
Maintenance problems aside, as Reclamation Day approached, morale was low, and new difficulties persisted. With some dwellers managing to hack into the vault's files and rumors of security strangling folks, the overseer's attention was elsewhere. Following the vault's reopening, she was tasked with tracking down and securing three nuclear warheads.
5 Vault 51
Like vault 76, most players should prove reasonably familiar with vault 51. Vault 51 housed 55 dwellers and acted as the hub for Fallout 76's battle royale mode, Nuclear Winter. Since Fallout Worlds release, vault 51 has been open to exploration.
Vault 51 was unique in one particular way; it didn't have an assigned overseer. Yet it did have a way to pick one, in the form of a ZAX 1.3c. This supercomputer was programmed to select a leader. After years of failed elections in which everyone voted for themselves, one dweller blowing themself up over ZAX's methods, murders aplenty, and an overall personal interest in escalating dweller's violent tendencies, ZAX started to create more dangerous scenarios that seemed more catered to its pleasure rather than electing an overseer.
After countless cycles, an overseer was chosen. ZAX's last man standing was named the overseer, but with no one to oversee, he grew increasingly depressed. ZAX even went as far as to deem him unfit and lock him out of most areas. Despite its programming, ZAX ran this vault as it saw fit.
4 Vault 79
Vault 79 was constructed in secret and housed 120 dwellers. The goal of vault 79 was to house something other than people; gold. The military took all the gold housed initially at Fort Knox and brought it to vault 79 for the sole reason of rebuilding America's economy after the bombs dropped.
Years after the vault was sealed, rumors of some prophesied treasure grabbed the hearts and minds of survivors and factions alike. After a stint with the secret service and the help of a specific vault dweller, the vault was sieged, leading to some gold being discovered.
3 Vault 94
Vault 94, initially introduced in the now vacant vault raids, is available in One Wasteland For All and can be explored at leisure. Half of the documented dwellers were locked out and couldn't enter in time due to a supposed door malfunction. The inhabitants that successfully arrived at vault 94 favored non-violence and faith. Also, in place of an overseer was a council system in which dwellers could vote on communal ideas.
The goal of vault 94 was for its pacifist favoring dwellers to be released into the wasteland one year after the bombs dropped in an effort to force them to alter their ideologies to survive. This vault, while equipped with bountiful resources, was without any form of weapons. This made it difficult for them upon being released into the new world.
After attempting to establish a relationship with a neighboring community outside the vault, the council was massacred for their G.E.C.K as it was assumed their hospitality had to be a trap. Soon after, from the wastelanders' mishandling, the G.E.C.K had a meltdown causing a rad-filled nuclear explosion.
2 Vault 96
Vault 96, while initially planned as a vault raid, first found its way into the game in the form of the Locked & Loaded update. Thanks to Steel Reign, it is now open to exploration. Vault 96 housed a small group of scientists and was touted as the An Ark for the Atomic Age. Its focus appeared to be fauna and cryogenics.
In classic Vault-Tec fashion, the true goal was to study and reverse the new postwar world's effects on fauna. Years after the team was killed in an escape attempt, a new inhabitant moved in and continued the vault's research. This new continued research led to the creation of FEV or forced evolutionary virus. This same virus introduced super mutants to the wasteland.
1 VTU Training Vault
Vault-Tec University was home to training and schooling detailing the Vault program but later became more vocational for Vault-Tec employees. This simulated vault helped educate employees and appeared as real as they get. This vault also had information detailing the experiments at several other vaults.
In the last of many test run proposals, the dean approved an experiment covering the downfall of a vault due to replacing food with a specific food paste. This food paste would cause an accelerated circulatory decline, but the dean still approved, knowing so. The Great War began in the middle of this test run, but that didn't stop it. After a death caused by the paste, dwellers rebelled against the one who proposed the experiment to the dean. He then called out to the wasteland for help that never came. After a failed uprising against him, everyone eventually perished from starvation, and the test vault remained closed.