Iacon

Iacon is the oldest and most important of Cybertron's city-states, and in every G1 telling it is the Autobot capital. It houses the Hall of Records where Optimus Prime worked before the war, Alpha Trion's workshop, the Autobot High Council chamber, an observatory, and, in most accounts, the shaft down to Vector Sigma. When the cartoon flashes back to the Golden Age, Iacon is the shining gold city that gives the era its look.

The war reaches Iacon early. In the backstory the cartoon assembles across The Secret of Omega Supreme, The Key to Vector Sigma and Five Faces of Darkness, Megatron kills the sitting Autobot leader in a strike on one of Iacon's outer cities and keeps it quiet, while Alpha Trion works in secret on a reconstruction process for the war he can see coming. That process produces Optimus Prime from the mortally wounded dock worker Orion Pax, and Iacon becomes the command centre of the Autobot war effort.

For four million years after the Ark departs, Iacon is the pocket of resistance Shockwave never fully closes. Elita One's Female Autobots operate out of the ruins and the tunnels beneath, raiding Decepticon energy stores, which is where Optimus Prime finds them in The Search for Alpha Trion. By 2005 the Decepticons have taken the city and the whole planet, and the Autobots have been driven to Earth. Rodimus Prime's forces retake it after Unicron's defeat, and by 2006 Iacon is again the Autobot capital, the place the Quintessons keep trying to infiltrate throughout the third season.

• Iacon is the only Cybertronian city named consistently across the Marvel comics, the cartoon and every later continuity.
• The Hall of Records, Maccadam's Old Oil House and the Observatory of Iacon are all fixtures of the city, though the bar and the Hall are prose and comic additions rather than cartoon locations.
• In the cartoon's Golden Age flashbacks Iacon's gold colour is a deliberate production shorthand: healthy Cybertron is gold, war-ruined Cybertron is grey-blue.
• Beast Machines later established that the Maximal city of Cybertropolis was built directly on top of Iacon's ruins, making the capital a literal foundation layer.