We walked in and waited an hour for next group. 7/10/18
We scheduled about a month in advance for our 3 person group. We were joined by 2 walk-ins.
I scheduled for my 4 person family 2 months in advance because I wanted to be sure it would fit into our trip itinerary, but I think the 2 person group who joined us on our tour walked in and signed up that day.
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