From Bulbapedia, the community-driven Pokémon encyclopedia.
Pokétopia is the large city where Pokémon Battle Revolution takes place. Aside from having all the normal facilities of a city, such as streets, buildings and a harbor, Pokétopia is also home to ten different Colosseums, each with their different rules and a leader to run those facilities. In this, it is highly similar to the Battle Frontier, albeit larger.
The design of the technologically advanced city is very similar to LaRousse City.