Vault of Tomorrow

From Memory Alpha, the free Star Trek reference

The Vault of Tomorrow (also the Altar of Tomorrow) is located in the Chamber of the Ages on level 23 of the Janus VI colony. This vault is where millions of Horta eggs are stored and watched by the mother Horta. In 2267, miners of the colony inadvertently destroyed thousands of eggs when opening up level 23, causing the mother to go on a murderous rampage throughout the colony. (TOS: "The Devil in the Dark")