Azkaban
From FenWiki
Somewhere in the Kupier Belt; for those rare times where a criminal hasn't upset the 'Danes, community service to the terraforming groups isn't enough, and the death penalty is either too extreme or not practiced by the affected Faction.
A copy of the Whole Fenspace Catalog is kept in the Warden's safe, so that the Catalog has a chance of surviving any system-wide catastrophe.