The option by foot is via a set of steps that are positioned on the slope between Crissy Field and the Fort. These lead to other paths that eventually lead to the bridge. Keep your heading toward the golden gate to get there. Adults and older kids should have an easy time. Smaller kids/toddlers may tire. It's not a difficult or long walk. Golden gate sf side should be approachable from fort point within 20 or so minutes (or less)
Fort Point sits under the Golden Gate Bridge and is not attached to it. There is a paved trail that connects them if you would like to leave your vehicle parked at Fort Point.
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