Ark

The Ark was the vessel used by Optimus Prime and his band of Autobots four million years ago. It crashed on Earth at what would later be known as Mount St. Hilary, disabling all Transformers aboard. It wasn't until 1984 that a volcano eruption woke them up, causing the war to enter its latest stage.

After serving as the Autobot HQ for years, the Ark was eventually rendered obsolete by the creation of Metroplex. Although most of its systems have been removed, the Ark remains an important cultural, if not strategic, asset for the Autobots.