|Points of interest||
The planet entered an ice age in 5,000 BBY. Glaciers covered the normally-warm equatorial regions of the planet, while solid ice locked the poles in perpetual winter. In order to survive, the Chiss built energy-efficient warrens beneath the ice, as close to the warmth of the inner planet as possible, with underground carriage travel routes to connect the various underground sections of Csilla. The iceways were bored through the bedrock of the planet, so that they were unaffected by the shifting ice found on the planet's surface.
Locked in an ice age for millennia, Csilla forced many socioeconomic and technological changes upon the Chiss, but few physical changes. Contrary to beliefs in a link between the Chiss skin color and the Csillan temperature, scientists have concluded that the Chiss’ blue skin is caused by a mineral found in the Csillan hydrosphere.
Csilla was the capital of the Chiss Ascendancy. It was also home to the Expeditionary Library. Grand Admiral Thrawn was born here.