The Autobot Mausouleum is the final resting place of the chassis and servos of fallen Autobot heroes. It is a large barge set adrift in deep space. Inside, you can find the memorial known as the Veil of Remembrance.
The Transformers cartoon
While being pursuied by Galvatron, Rodimus Prime and his crew had to ditch their Starship and take refuge on the Autobot Mausoleum. Inside, they were surprised to find Optimus Prime seemingly alive, if not entirely well. In truth, he was little more than a reanimated corpse, courtesy of the Quintessons. The Autobot Mausouleum was destroyed when the zombie Optimus Prime set the self-destruct.