North Cave

A cave located within the Frozen Zone, a freezing cold section of South Island, where Sonic first hid the six Chaos Emeralds from Doctor Robotnik. They were safe in the North Cave, the cold temperatures kept the Emeralds stable, until Captain Plunder stole them. After Sonic retrieved the Emeralds, he kept them in a special sub-zero temperature box in his secret base, their location became a mystery once again.