PaperMariottydV0.0.1.zip is an alpha file of the Minecraft map Paper Mario: The thousand year door. It was published on March 12, 2013 and is 25.1 MB in size. Pre-release builds can contain bugs — back up your world before installing. For the full description, screenshots and every other version, visit the Paper Mario: The thousand year door map page.
How to install: Extract the .zip and move the world folder into .minecraft/saves; the map then appears in your Singleplayer list.