We went in a cab to a local beach. There were too many people trying to sell us junk non stop. My son did get to jet ski for a decent price. I think it was called, Carlos & Charlies? The water was not very clear and there were lots of rocks.
Carvetubing R"us" excellent tour with David. An excursion not to be missed the best price and best tour by far. Read the review on Trip Advisor you can not go wrong. Much less than carnival and a much better tour.
It felt like they packed as many people in the bus as they could and ran from stop to stop trying to sell things. I did like the last stop being the beach and the driver offering to come back in a few hours to take us back to port. I talked him into a lower fare but I still think it was too high for what they do.
More 
