The Ice Cavern is a mountain cave that is first seen in the episode "Monster Buddies".
The first shown part of the cave is a huge room with snow covering the ground. A large gray-blue door is located on a wall. A key feature of the cavern is the sharp, icicle-like formations on the walls and ceilings. There are many blocks of ice that inhibit passage into the deeper parts of the cavern. Further into the cavern are smooth tunnels, narrow crevices, and rooms with towers of round rocks stacked on top of each other.
Deep within the cavern is the room where the Shooting Star is kept. The star itself resided within a shallow pool of icy water. This room was notably pink in color due to the reflection of the light from the Shooting Star in the water.
At some point in history, Gems stored the Shooting Star deep within the cavern for an unknown reason.
In "Monster Buddies", the Crystal Gems went to the cavern to retrieve the Shooting Star for their own use. Obstacles such as the Ice Monster and falling debris kept them from this goal. It wasn't until Steven tamed Nephrite that they were able to travel further into the cave with the help of Nephrite's acidic abilities to clear a path.