Timmadome

The Timmydome is a massive stadium that Timmy Turner wished for in the episode One Man Banned.

Information
When Timmy wished to be the best musician in the world, he started to become extremely greedy and fame-crazed. In madness he eventually wished for a stadium that was so big it would fit everybody in the world in it, so that he could have the biggest concert ever. The stadium was eventually destroyed, along with the rest of the world, when Timmy attempted an ill-conceived come back after his magic failed, causing the entire stadium to collapse from his horrible music.

Description
Cosmo and Wanda's wish first shifted the continents of the world together so they resembled the form of Timmy's face, and then everyone on Earth poured into this massive structure which had sprung from the Earth and was many times the Earth's size. It was colored purple and blue with a sparkling retractable roof. Inside the stadium were seats all facing a large purple stage in the center of the structure.