From Zelda Wiki, the Zelda encyclopedia
Minish Portals, either hidden or visible, can be accessed by Link throughout The Minish Cap. These portals allow Link, with Ezlo, to turn into a Minish-sized person. The portals allow Link to access different areas and after swallowing a particular nut, allows communication with the Minish. Minish Portals can also be used to make Minish Link normal size again. Once Link is of Minish size, he cannot return to normal size without using a Minish Portal.
Types of portal
|Trunk portals are one of the most common portal types in the overworld, and are found in most areas.|
|This type of portal is only found inside dungeons (with the exception of Deepwood Shrine and the Temple of Droplets which have no portals, as Link remains Minish-sized throughout).|
|Pot portals are found inside houses and shops in the overworld. To be used, they must be upside-down. The Cane of Pacci may be required to flip them over.|
|Stone portals are found in the Mount Crenel area of the overworld.|
|The entrance of the Temple of Droplets are a special type of Minish Portal.|