The dominant of Crystal Empire is the enormous tower, going as high as 150 meters. Only the lower quarters are being used, mostly because no one wanted to go so many stairs. Building itself is the emitter for the shield that covers whole empire, effectively protecting its citizens from eternal winter. When the shield is turned on, it causes a disturbance in magnetosphere of the planet and beautiful aurora borealis like effect can be seen in places as far as Canterlot. No one did a proper study what effects it has on the planet itself.