Earth

Earth is a rocky planet orbiting the Sun, and the third planet in order from that star. The Teenage Mutant Ninja Turtles were born on Earth and usually dwell there. Some of the most important countries on the Earth in the Teenage Mutant Ninja Turtles stories are the United States of America and Japan. The dominating inhabitant species on Earth are humans.

Appearance and depiction
In most incarnation of the Teenage Mutant Ninja Turtles, villains (mostly Shredder and or Krang or the Kraang, or the Triceratons) are always trying to take over the Earth or at least parts of it, resulting in the turtles' feeling it's up to their duty to stop them.