Geography
A series of isles that are difficult to chart due to the ever changing nature of the Vault. Many have wildly different and even alien environments which defy any real classification.
History
Ostensibly created by the Ardruid Unknown as a place for the Ardruids to safely test and develop their astounding magics and sciences without endangering the greater inisa. Many mysteries surrounded the islands within the Vault, but it was not until AoA 2808 RE that the interior was able to be explored by the intrepid council of Ard Righ Cian an Nathair and his Council of the Teanga Beithir.
Even so, what miracles and horrors they witnessed were a small fraction of what is suspected to be within this island chain. What further mysteries and revelations still linger within is anyone's' guess. However, as a workshop of the Ardruids, many believe them to be suitably powerful objects, divine structures or insane experiments. Of what little expeditions have launched, very few return and their tales carry the weight of legends and madness.