The Expeditionary Library was a huge, underground library located on Csilla and maintained by the Chiss Expansionary Defense Force. The library contained written information on virtually every planet, moon, and star system ever encountered by the Chiss. It was unusual, not because it was underneath the ice, but because every volume contained in the library was handwritten, in an attempt to protect them from sudden ice-storms.
- The New Jedi Order: Force Heretic II: Refugee (First appearance)
- The New Jedi Order: Force Heretic III: Reunion (Mentioned only)
- The New Jedi Order: The Unifying Force (Mentioned only)