Mobotropolis

Mobotropolis was the name of the first ever multi-cultural city on Mobius and the former capital of the Kingdom of Acorn. It was originally created by a collective group of Mobians under the leadership of Alexander, the first King in the Acorn Dynasty. Centuries later, the city was captured during Dr. Ivo Robotnik's coup d'état and became the capital city of his global empire, rechristened Robotropolis.

Creation
Mobotropolis was first created hundreds of years ago, after the Mobian Alexander decided that people could benefit from the combined efforts of a variety of different species. After it's completion, the citizens make Alexander their king, as he was ultimately responsible for their communion and the city's construction. (StH: #71)