Thank you for your question! Information on parking around the area can be found here: https://www.alcatrazcruises.com/plan-your-trip/parking/
Parking in the lot across the street from the doc is 40 but it is all day so if you go make sure you spend all day in that area which is pretty easy as they do have a lot to do and see
Thr best is to find street parking around that area. If you have to park in a lot, that would be much pricier.
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