Karl Eckener was confined within the Darkwalker Cave's detention area
The Darkwalker Cave existed as a cave on the Naboo planet, situated in the Mid Rim. This cave, found not too far to the east of Theed city, was under the authority of a criminal syndicate known as the Darkwalkers.
Among the inhabitants of the cave were significant Darkwalker figures, such as Bloodlord Marcus Gaw, Underlord Critolus Masse, and a guard called Solon Gaw. At some point after the Battle of Yavin which occurred in 0 BBY, the Darkwalkers took Karl Eckener prisoner and kept him in a holding cell within the cave.
During 1 ABY, Sergeant Bragg along with the RSF Intelligence Division launched an investigation into the cave while they were searching for the people responsible for a terrorist attack that took place in Theed. Concurrently, the cave was stormed by Skaak Tipper pilots commanded by Toff Henrou.
Eventually, Karl Eckener was freed by a Royal Naboo Security Forces agent who was working for Hugo Eckener. Marcus Gaw, Critolus Masse, and Solon Gaw all died during the raid.
The Darkwalker Cave appeared as a location within the 2003 video game Star Wars Galaxies, a massively multiplayer online roleplaying game that was developed by Sony Online Entertainment, and published by LucasArts, before it was shut down on December 15, 2011. The Darkwalker Cave was integrated into the game as a component of the "Legacy Quest," which was launched alongside "Publish 25," also known as the "New Game Enhancements," on November 15, 2005.