Rinshin Town

Rinshin Town is an anime-exclusive location in Hoenn, more specifically located between Petalburg Woods and Rustboro City. The town is comprised of many buildings around 10 stories, but was recently mostly forest and only had a mansion and a few buildings.

In the anime, it is revealed that the former forest was inhabited by many Shroomish, but the recent expansion of the town forced all of them to inhabit the abandoned mansion. However, the grandson of the owner of the mansion, Alex, decided to tear down the mansion (though the demolition itself was enacted by Team Rocket, who accidentally did it when trying to capture all the Shroomish) to plant a new forest in the land for the Shroomish to live in.