We have taken both the public ferry from Marigot and a private ferry from near the airport on the Dutch side, done it many times. I would suggest hiring a driver, hitting a beach or two (Shoal Bay), maybe checking out a resort or two and having lunch somewhere. It is not an inexpensive day but a nice diversion and contrast to SXM. I have never personally rented a car but a SXM taxi driver friend who went with us a couple of times did rent and drive, but I prefer the taxi for Anguilla.
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