Ondstanda
The Ondstanda was a fictional volcano located on the planet Ardani, created by Thaddeus Troi-Riker. The volcano could be entered through a cave entrance on its southwestern side.

This volcano was located in the territory of the Karvanno. 

Even after the death of her son, Deanna Troi kept the drawings of the maps of Ardani, one of which had labeled the location of the Ondstanda. ()
Fictional locations