World 8 (Super Mario 3D Land)
From the Super Mario Wiki
World 8 is the eighth and final normal world that Mario travels to in Super Mario 3D Land. The setting of this world is a volcanic area. Crags and volcanoes are found in the background, while the lava below creates a red mist. World 8 contains eight levels and no Toad Houses or Mystery Boxes unlike other worlds. This world also consists of two areas, the first containing five levels and Bowser's first castle, and the second containing the sixth level and Bowser's second castle, which is considerably larger than the first as it takes up the entire second part of World 8.