Don't do the Saucalito excursion - there isn't anything remarkable about the city. Instead explore pier 39 and Fisherman's wharf on your own. We observed Segway tours but didn't have the time to take one. The Alcatraz tour is within walking distance from your dock and at only $26 is a bargin.
We took a 60 minute Pedi-bike tour into the city. Our biker was very nice, stopped when and where we asked and took us into/thru the park. Definately recommend.
We used the 90-minute Victoria hop-on/hop-off bus. I would rather have taken the Gray-line hop-on/hop-off bus instead. When we got off the busses weren't on schedule and very crowded, just not enough.
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