Oregon

From Teletraan I: The Transformers Wiki

Oregon is one the states that make up the United States of America. It may be prone to attacks by that big green, fire-snortin' lizard...as well as massive battles involving giant robots

[edit] Marvel continuity

The volcano where the Ark crash-landed and rested was located in this state, which is also home to the Witwicky family. Most events on Earth in the US comic take place there unless it's stated that the characters have travelled to another location.

[edit] IDW continuity

Starscream had a command bunker there.