World of Kamen Rider

The World of Kamen Rider (仮面ライダーの世界) is the version of reality where Kamen Rider takes place. It is where Ambassador Hell of Dai-Shocker originally came from.

It was presumably home to an alternate version of the Double Riders. This A.R. World was not visited by the Hikari Studio during the Kamen Rider Decade TV series, but they could have visited it off-screen after the conclusion of the Rider War and the events of Kamen Rider × Kamen Rider W & Decade: Movie War 2010. Indeed they have the opportunity to do so as the Hikari Studio is left free to travel the A.R. Worlds as of the end of Movie War 2010.

In the movie Super Hero Taisen, Doctor G describes Dai-Shocker as the union of organizations from the Rider World (ライダ界). Material related to the movie also uses the names Kamen Rider World (仮面ライダ界) and Kamen Rider World (仮面ライダー世界) to describe this version of reality where all Kamen Rider tv series take place, one after another. The movie itself doesn't specify where the action is taking place specifically, but it features characters going from one location to another through Kamen Rider Decade's dimensional walls.