Rogueport

Rogueport is the fictional town in the Mushroom World, seen in Paper Mario: The Thousand Year Door. Its shown to be a port city surrounded by a greater world separate from the Mushroom Kingdom. As its name implies, Rogueport is a criminally run town with two gangs and multiple bandits. It does have a classier Eastern Side though.

The Sewers
The Rogueport sewers are long tunnels of piping stretching several feet below the surface.

Name Origin
"Rogueport comes from two words: Rogue and Port. A rogue is a criminal or ruffian, and a port is a seaside town. Rogueport follows both paths.