RetroDimmsdaleville was an alternate universe with Retroville and Dimmsdale combined together. It was created and ruled by Shirley in Jimmy Timmy Power Hour 3: The Jerkinators. He sucked up areas and inhabitants from Dimmsdale and Retroville and sucked them into RetroDimmsdaleville. When Jimmy and Timmy apologized for their actions towards Shirley, the dimensions were put back to normal and Shirley opened up his own pizzeria in Dimmesdale.
- Everyone who lives in this area are in their Butch Hartman designs. Including the ones from the Jimmy Neutron universe.