From Guild Wars 2 Wiki
Mystic Portals are one-way gates found in the Eternal Battlegrounds that take you to Obsidian Sanctum, home of the jumping puzzle of the same name. There is one portal for each keep in the Battlegrounds, found in different locations:
- The northern keep (Red World Overlook) Mystic Portal is underground, near an area known as the "secret passage".
- The south-west keep (Green World Lowlands) Mystic Portal is just to the north of the main building.
- The south-east keep (Blue World Valley) Mystic Portal is underground, through a passageway in the south-most part of the grounds.