When Daniel Witwicky and Grimlock wandered off from a diplomatic event the Autobots were hosting, they found themselves in a room which transported them from Cybertron to Menonia. Upon discovering the strange environment that they were in, Grimlock speculated that they were in California. Daniel pointed out that California, while strange, was not that strange.
Dreamwave comic continuity
Megatron had secreted Devastator in the San Francisco Bay years ago, and reactivated him to distract the Autobots while his metal virus cyberformed Earth. San Francisco suffered heavy damage from Devastator, and then even MORE damage when, after Optimus Prime defeated Devastator, the rest of the Decepticons arrived and another fight broke out. In the end General Hallo tried to nuke the city to wipe out the Transformers, but Superion detonated the warhead over the ocean. While San Francisco wasn't vaporized, it WAS hit with a tidal wave caused by the explosion, causing further damage to the already ruined city. Apparently, Pat Lee doesn't like San Francisco.
Movie continuity family