Prison Island is the smallest of the five islands of Riven.


Gehn cut down the Great Tree to create paper for linking books, after Atrus trapped him on Riven. Over time, the instability of Riven caused the islet to drift far away. The Moiety had no information about what was on the island.[1]

Gehn initially used the structure as his private office.

Gehn trapped Atrus's wife Catherine in a prison he built on the top of the Great Tree's stump. Nelah was allowed to meet her.[1] Gehn could spy on Catherine from his Survey room on the Survey Island.


Riven PrisonObservation

Observing Cathrine's quarters on Survey Island.

It was located so far to the northeast that it couldn't be seen from the other islands.[1]

It corresponds to the location where the enormous Great Tree was growing.[1] Gehn built habitable quarters inside and above the stump. Atop the installation is a rotating apparatus.

A walkway connects the islet to a Fire-Marble Dome, marked with the symbol for BLUE.


The island is not physically connected to the rest of Riven; it can only be accessed via a linking book found in 233rd Age, and one can leave it only through the rotating dome.


  1. 1.0 1.1 1.2 1.3 Catherine's Riven Journal