Marion City
From Bulbapedia, the community-driven Pokémon encyclopedia.
Marion City is an anime-only location said to be in Johto featured in Celebi and Joy.
At first, the city was very modern and not embracing of its old traditions, even preparing to demolish a historic Pokémon Center to make way for something new. After Ritchie had gone back in time and changed history, the city also changed into a city that embraced its old traditions, even going as far as restoring the historic Pokémon Center.

