Pipe Land

Pipe Land  (alternatively Pipe Maze or Tube City ) is the seventh world of Super Mario Bros. 3. Pipe Land consists of nine levels, two Fortresses, three Toad Houses, two Spade Panels, a king's palace, and two special Piranha Plant levels. The world consists of many islands linked by a confusing network of pipes, and the islands resemble Warp Pipes. The levels in this world often have complex pipe networks within. The kingdom is known to have landscapes, such as plains, deserts, and more, with several pipes. The king wears a viking's helmet and overall resembles a nordic viking.

The labyrinth world of Pipe Land is conquered by Ludwig von Koopa, who turns the king into a Venus Fire Trap (or a Yoshi in the remakes).

According to Super Mario Advance 4: Super Mario Bros. 3, Pipe Land is located to the east of Grass Land, and to the west of Ice Land.

The Adventures of Super Mario Bros. 3
In The Adventures of Super Mario Bros. 3, Pipe Land, which was again sometimes referred to as the Pipe Maze, appeared in a few episodes. Underneath Pipe Land is vast underground maze filled with pipes and rivers. It is populated by various enemies such as Thwomps, Boo Diddlys, Venus Fire Traps and even Boom Boom.

Oh, Brother!: Using the Power Shower, Kooky and Bowser were scheming to wash all the coins floating around in the underground Pipe World (presumably another name for Pipe Land or a related area) into a dungeon where they could collect them. When the Power Shower sprung a leak, Kooky captured Mario by pulling him through the Pipe World using his Plumber Pole. Kooky then hypnotized Mario using his Lame Brainer so that he would mindlessly repair the invention. Luigi attempted to swim through the Pipe World to rescue Mario, but after a being chased by a Boss Bass, he returned to Toad's House to don a Frog Suit. As Frog Luigi, Luigi eluded all the enemies in the Pipe World and found his way to the Koopas' dungeon. After Luigi rescued Mario and defeated the Koopas, the Power Shower was dismantled, and all the stolen coins were returned to the Pipe World.

Misadventure of Mighty Plumber: In this episode Bowser wanted to rob Pipe Land's Coin Treasury. After Cheatsy brought Mighty Plumber to life from the TV, Bowser tricked him by saying that Mario and Luigi were trying to rob the treasury. Mighty Plumber followed Bowser through Pipe Land's underground maze, keeping Mario and Luigi out of Bowser's hair. After Bowser plundered the vault, he locked Mighty Plumber inside along with Mario and Luigi. With some help assistance from Mario and Luigi, Mighty Plumber escaped, took the coins back, and was returned to the TV. Mario and Luigi later returned the coins to the treasury.

Misadventures in Babysitting: The Pipe Maze was also featured in this episode. Junior, a spoiled child from Brooklyn whom Mario and Luigi accidentally wound up babysitting, found a warp leading to the Mushroom Kingdom. There he quickly befriended Bully, Cheatsy, and Kooky. The Koopalings used Junior as bait to lure Mario and Luigi into a volcano. However, they Koopalings betrayed Junior and tossed him into the Pipe Maze, where he was scared off by various enemies. Eavesdropping on the Koopalings, Mario and Luigi learned about where Junior went, and traveled into the Pipe Maze to find him. At the same time, Kooky began filling the Pipe Maze with lava. However, Mario and Luigi were able to find Raccoon Power, and were able to use it to free Junior from the Pipe Maze.

Nintendo Comics System
Pipe Land is the setting of the Nintendo Comics System story The Revenge of Pipe Ooze!, which reveals the world hosts The Annual Dirk Drain-Head Role-Playing Game.

Nintendo Adventure Books
One of the Game Overs in Leaping Lizards has Luigi end up lost and disoriented in Pipe Land if he falls into a body of water and is sucked into a pipe due to having an Anchor in his pocket.

In Pipe Down!, Ludwig von Koopa sets up a base in the Pipe World (possibly Pipe Land or a similar location) and intends on debuting his basketball-themed opera, Dribbling Beauty, there; using a pair of magic shoes sent to her as a birthday present, Ludwig abducts Princess Toadstool to star in the opera as the "Prime Slamdunkerina". Along with a stage, Ludwig also has a Piranha Plant string quartet, a giant magical pipe organ, and a jukebox in his secret chamber. The Mario Bros. can reach Pipe World by either going down a tunnel beneath the Mushroom Palace, or by using one they discover in the Koopahari Desert.

Trivia

 * A remix of Pipe Land's map theme plays in the stock menu in Fortune Street.