We were originally booked on the Muir Woods Combo Tour, but the day before they called to cancel and offered us the five hour City Tour that was basically the same thing without Muir Woods. I suspect they cancelled Muir Woods due to not enough participants. They were very pleasant and extremely professional, and the difference in price between the two tours was immediately refunded to my credit card.
Pros: You see a lot in a comfortable setting
Cons: Not enough time in some spots, too much in others
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