Mount Oyster, also known as Oyster Peak, is a mountain mentioned in the episode "I ♥ Dancing."
It is unknown what it actually looks like, but SpongeBob owns a snow globe version of it. It is probably a mountain with a giant oyster on it. The mountain is purple.
Role in episode
Squidward tells SpongeBob to run all the way up to Mount Oyster and back. SpongeBob runs all the way there and comes back with a snow globe of Mount Oyster for Squidward.