The Surface of the planet Earth, refers to the regions of the Age of D'ni where the native humans thrived. It remained inaccessible to the D'ni people for the most part of their history, who occupied a Cavern deep below the surface.
Early in their history, the D'ni (perhaps the Guild of Miners although the Guild could not have existed back then) built a ventilation shaft network in order to provide the Cavern with fresh air. This was the only known time that the D'ni reached the surface, and there were rumors that some fled there, preferring the surface than the hard life inside a cavern.
Identified on KIs as D'ni - Riltagamin, literally meaning "D'ni - Unknown," the identifier for all areas the D'ni were unaware of. The Cleft is a fissure of volcanic origin near a dormant volcano. It is near the exit of the Great Shaft.
After the downfall, Anna took her son Gehn with her to the Cleft, and established a living area, surviving through the careful capture of water and occasional trading with passing caravans. After Gehn's departure, Anna lived here with her grandson, Atrus, until he was taken away by Gehn, his father, to D'ni. The novel Myst: The Book of Ti'ana implied the Cleft was somewhere in the Middle-east, near an evidently Arab or Ottoman city called Tadjinar, but Uru: Ages Beyond Myst, considered more canonical than the books, puts the Cleft in the desert near Eddy County, New Mexico, United States, on the property of Jeff Zandi. Due to the conflicting references, it could be up to debate. Its location suggests that the cavern system that supports the D'ni empire is somehow connected to the Carlsbad Caverns.Tomahna is the new home of Atrus, Catherine and their daughter Yeesha. It is located within a few miles of the Cleft, but in a geographically distinct area. Tomahna houses the new library of Atrus, and is the third home of Atrus and Catherine, after Myst Island and Chroma'Agana. A small part of Tomahna is seen in Myst III: Exile. In Myst IV: Revelation, the player is able to explore Tomahna in its entirety.
The Lodge Edit
The Lodge was the home of Anna and her father, during their days as surveyors of the area near the Cleft.
Not part of the D'ni empire, the Bahro Caves (also known as Rudenna) are important to the Bahro (beast-people). Explorers have speculated that they may be the original homes of the Bahro, but there is no other evidence to support this. The Bahro Caves play an important role in the game Uru.