Portal.zip is a release file of the Minecraft map kind of Portal, made for Minecraft 1.16.5. It was published on August 13, 2021 and is 2.2 MB in size. For the full description, screenshots and every other version, visit the kind of Portal map page.
How to install: Extract the .zip and move the world folder into .minecraft/saves; the map then appears in your Singleplayer list.