Kaon

Kaon is the Decepticon capital city, located in the southern hemisphere of Cybertron from the Transformers franchise. Decorated with wickedly sharp and intimidating gothic structures like dagger-shaped buildings, Kaon became an extremely large armored fortress of Kolkular housing armies of Decepticon foot soldiers as well as high-ranking officers including Megatron, Starscream, and Soundwave.

Kaon Prison
Kaon Prison is a large penitentiary complex used to incarcerate and execute Autobot prisoners of war. In the early days of the war, Sideswipe, Optimus, Bumblebee, and a squad of other Autobots purposely got themselves arrested so they can infiltrate the prison and save an imprisoned Zeta Prime. However, Zeta eventually died, the events of torture occurring in the prison leading to the birth of Optimus Prime. Soundwave was the warden of the facility after the core of Cybertron was infected.

Gladiatorial pits
The gladiatorial pits are wide coliseums where brutal gladiators battle to the death. Meanwhile, sadistic spectators watch in entertainment at the vicious battling. It is the very place that formed Megatron into the barbaric tyrant he's known for and where he met his eternally loyal servant, Soundwave.

Soundwave's workshop
Main Article: Soundwave's Workshop

Soundwave's workshop is considered to be both a junkyard and a laboratory. It is where the Decepticons dump other corpses and war debris, basically using it as a large trashcan. However, Soundwave cares not and uses the scrap for his enigmatic experiments. It was where he rebuilt Megatron.