Autobot Road
From MediaWiki

The Autobot Road (サイバトロンロード Cybertron Road) is a series of underground passageways and highways which connect various Autobot headquarters all over Earth.
Fiction
Fight! Super Robot Lifeform Transformers manga
Optimus Prime revealed to Kenji that the Autobot Road is a series of highways located 2,500 meters beneath Earth's surface. It was used to connect the Autobots to secret bases located across the globe and explained how they were able to drive from one continent to the other so quickly. Prime also revealed that the concept of the Autobot Road was Ultra Magnus's brainchild. Fight! Super Robot Lifeform Transformers #4
Notes
- The Global Space Bridge from the 2001 Robots in Disguise cartoon is similar to the Autobot Road. In fact in the original Car Robots cartoon, it was called the Cybertron Net (サイバトロンネット Saibatoron Netto). They could very well be one and the same in the Japanese Generation 1 cartoon continuity.

