Rogueport

Rogueport is the main town and starting point in Paper Mario: The Thousand-Year Door. Mario comes here at the beginning of the game to meet Princess Peach because she found a magical treasure map. In Rogueport, there is an item shop, the Lovely Howz of Badges, the Pianta Parlor, and two entrances to the Rogueport Sewers.

The town is divided into five sections, the north side, the west side, the main plaza, the docks, and the east side. Mario will be moving through here constantly throughout the game. He can also find his brother Luigi in the different areas of Rogueport during different chapters.

It is unknown if Rogueport and it's surrounding areas are a part of the Mushroom Kingdom.

Rogueport in detail
North Side: The Excess Express, the Glitzville blimp, and sometimes Luigi.

West Side: Don Pianta's room, Peeka's Westside Goods store, the Pianta Parlor, Lucky with the Lottery Picks, and a grate to Rogueport Sewers.

The Plaza: Zess T., Toad Bros. Bazaar shop, Charlieton, the Lovely Howz of Badges, Podley's soda bar, and the gallow (noose platform).

The Docks: Lumpy, a Boat Mode platform, Cortez and the Black Skull (once Mario completes Chapter 4), and Pa-Patch (before Chapter 4).

East Side: Professor Frankly's house, Merlon's house, the pipe to Rogueport Sewers, Gus, the Robbo Gang's hideout, the Trouble Center, Grifty, and Bobbery's house.