Diet Cola Mountain

Diet Cola Mountain is a volcano in the 2012 animated film, Wreck-It Ralph. It was the home and secret hideout of Vanellope von Schweetz during King Candy's fifteen year reign of Sugar Rush.

Background
Diet Cola Mountain is a soda bottle shaped volcano with a pit of boiling hot Diet Cola instead of lava. There are stalactites that sometimes fall from the roof of the volcano, causing fizzy eruptions! Diet Cola Mountain was home to Vanellope, who lived in a secret un-programmed hideaway inside the mountain (by entering through two sugar free lollipops at its base) before she moved into King Candy's former castle. There is an incomplete racetrack within the mountain, suggesting that the mountain was intended to be a bonus level, but the game creators never got around to finishing it; this is loosely confirmed by Vanellope, as she is only guessing it is true.

Wreck-It Ralph
After breaking into King Candy's kart factory to build a kart, Ralph and Vanellope are pursued by the king and his henchmen. They manage to evade them by escaping to Diet Cola Mountain, where Vanellope introduces Ralph to her shabby home. After learning more about Vanellope and her motivation to race, Ralph creates a racetrack inside the mountain to teach her how to drive.

Later on, Sugar Rush is taken over by Cy-Bugs—one of which eats King Candy, turning him into a cybernetic monster bent on taking over the arcade. Ralph formulates a plan to erupt the mountain and use the lava as a beacon to defeat the monsters. At the mountain's summit, he is confronted by King Candy. The two battle, and King Candy lifts Ralph high above the mountain. Ralph breaks free, and the impact of his fall erupts the mountain. As planned, the lava attracts the Cy-Bugs and King Candy to their deaths, saving the arcade.