Vault 68 is one of the Vault-Tec vaults. It was designed to contain 999 men and one woman.
As part of the vault experiment, of the one thousand people who entered, one was a woman and the rest were men. The location and status of this vault are unknown.
Vault 69 is Vault 68's counterpart which contained 999 women and only one man.
Vault 68 does not appear in any game and is mentioned only in the Fallout Bible. It was also to be mentioned in Fallout 2, but the relevant content was cut.
|The following is based on unverified behind the scenes information and is speculative and may not be accurate.|
Vault 68 is a reference to the sexual position mentioned in the Kama Sutra, in which position 68 is for the sexual pleasure of the woman.
|End of information based on unverified behind the scenes information.|