Ongoing local discussion about replacing the Evergreen Point Floating Bridge made me wonder about the life span of the Golden Gate Bridge. That icon of San Francisco and the U.S., could it survive for hundreds of years? It is, after all, a steel object in a notoriously foggy location. But as a beloved symbol, if it did need to be replaced, it would likely be kept as the original design no matter how bridge technology has evolved. Or perhaps we’ll be using flying cars and can just keep the bridge preserved and unused after it loses integrity. The S.F. Chronicle had two answers to the life expectancy question. Dale Luehring, a former general manager of the Golden Gate Bridge district general manager said two hundred years. But Kary Witt, the current manager, said “more or less infinite” with proper maintenance.