I grew up in NYC and don't usually do ""tourist"" activities, but the Circle Line Downtown is really awesome. I took some friends from out of town to the Thursday Happy Hour Cruise and we all had a great time. If you want a guided tour, then the Circle Line from 42nd street has the full island circle tour which is quite comprehensive. However, if you want to just have a great time on the water, snap some pictures and take in the view, the downtown Circle Line is way better. Plus going down to the South Street Seaport is alot cooler than going to Times Square if you ask me!
Pros: Fun, inexpensive, great lor locals and visitors, bring a camera
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