There's places to board all over the city. We boarded down by pier 39. I can't remember the exact price but I want to say it was around $50 a person. It was worth the price. Get seats on top of the bus and make sure you have a hat or sunshade. Bring snacks and a drink too. Use the restroom before the tour starts as there are no restrooms on the bus. The tour is long. You can get on and off the bus at any of the designated spots all over the city. Although, if you get off near the golden gate bridge it is hard to get back on with all the crowds of people. If you follow the above advice your tour will be way more enjoyable. My husband and I took our 4 children age 1-9 and had a wonderful time.
You can board at any of their stops along the tour route. We found it best to buy tickets at their main office..
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