Golden Gate Bridge

That's what I'd have done - just sit in my car with the doors locked, hoping that nobody with guns or powers noticed me!

Maybe I'd get out if I saw some idiot trying to jump and make a swim for it, and save a life by stopping them. The currents around Alcatraz are deadly.

I personally think that not too many of the regular people on the bridge survived. After all Magneto slammed the bridge into the island and then the war started. We don't see what happens to the "regulars" as it wasn't important to the story. But, as the war progressed and the mutants over ran the island, I am sure there were civilian casualties also. And, also, whose to say that when Jean unleashed her full power, she didn't disintegrate a lot of them?