The Material Plane is the dimension in which Istria exists.
The Feywild is the realm of magic and spirits; it is a parallel dimension of the Material Plane.
The Shadowfell is the realm of gloom and darkness; it is a parallel dimension of the Material Plane.
The Astral Sea is home to the Gods and their servants.
The Far Realm invades the cosmos from outside. It is a plane of madness and terror.
- Main article: Astronomy of Istria
- Main article: History of Istria
Istria is a planet which orbits around a binary star system. Istrians must undergo a migration every two years to accommodate the unique orbit of their homeworld. Istria has four continents. They are (in order of size) Arjkhann to the South, Oemberaen to the Northeast, Driestania, an archipelagous continent spanning the Istrian Date Line, and Il-etao to the Southwest.
Arjkhann was once the stronghold of Arkhosia. Its Northwestern most corner had been reduced to a massive sprawling desert.
Oemberaen once held the Tiefling empire of Bael Turath. Its Southeastern coast holds the Cape of Atmaut, where the events of The Hand and the Eye took place. Just south of the Cape of Atmaut region lays Darksand Desert.
Driestania is a series of islands of greatly varying sizes. Its largest island, Dries, is located in Northern Istria. Ragna Island, West of the Istrian Date Line and away from most of Driestania illustrates the scope of the archipelago-continent.
Il-etao is the smallest of Istria's continents. Located west of Arjkhann, it has a largely different biodiversity than its neighbor.