It is a large, mountainous area that is cold and covered in snow. Despite being quite a difference from the normal landscape of Bikini Bottom, the frozen tundra is very close to the city, with it being implied that it only takes a few minutes to get to the Chum Bucket from it.
Role in episode
A lot of people from Bikini Bottom come here to have a race. During the race, SpongeBob, Patrick, Squidward, Mr. Krabs, Sandy, Gary and Karen get off guard from the race and are in the middle of this tundra. Later, when everyone finds out Plankton is trying to steal the formula, everyone decides they would head back there to stop him. They eventually do so and escape the frozen tundra.