My wife and I took the tour on the second level in the front seats. While most of the passengers in head of us headed up to the very top, we went through the second level to the seating up front. The views were very good from this vantage point. We took the longer tour that goes down the millionaires row of islands, then goes up the channel under the bridge that goes to Canada. The weather was great on the June Friday that we took the tour.
Important note: You don't need a passport to ride the UncleSam Tour boat if you stay on the boat and don't transfer to Canada on Heart Island. The boat does travel into Canadian waterway space, but if you don't get off the boat, you are fine.
Be sure to take the tour of Boldt Castle AND take the $2 extra tour to the Yacht Boathouse. These tours are well worth the cost. If you've toured the castle even a few years ago, there is constant renovation, and the newly finished areas are worth an new visit.
Current renovation activity is being done at the older playhouse castle near the entrance arch to the lagoon (this location is closed to visitors this year).
Back to the boat... my wife and I stayed in our seat the whole time we rode the Uncle Sam tour boat so I don't have any reviews on the snack bar, restrooms, interior spaces, etc... The tour guide does an excellent job describing the passing scenery and he even keeps up to date on the newest construction progress on many of the islands (and the owner's of the newly changed properties).
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