Fort Vorticon is the ninth level (in the official numbering) in Keen 3. It is an optional level, located in the Military Installation Island, in the same area as Fort Vorta Bella, Fort Vox and Fort Cavort (all of which are optional).
Fort Vorticon is one of the biggest (and probably one of the hardest) levels of Keen 3. It appears to be one of the most important military installations of Vorticon VI. It is completely underground and very well hidden, with its main entrance under a waterfall. It also has two missile shafts that can be used as entrances, and one of them is equipped with a missile ready to be fired. The missile is probably used as a defense measure, in case of a massive attack or invasion on Vorticon VI.
The Fort is manned by Vorticon Grunts, and consists of two separate areas: the main missile base, which is reached by the waterfall through a cave-like entrance (which contains the yellow keycard); and a secondary, much bigger area. The second area is accessible by the second missile shaft, and contains a strong laser defense system (consisting of 11 lasers protecting a vertical shaft). It also contains a pool for Youths, and a large system of tunnels after the yellow door, leading to the exit. In order to reach it, Keen has to collect a green and red keycards (there is also an optional blue keycard that is not required), and avoid not only the Vorticons, but also the balls and jacks bouncing in the tunnels.
The level also has a small "secret" area on top of the waterfall. It also features an Ankh in the inner tunnels.
See also List of Keen 3 levels.