The Yacht Club is on Bradley Point which is at least an hour from Hilton Head by boat unless you have a really fast boat. It is also a private club. You will need to check with club management at either your club or theirs to see if they have a reciprocal agreement
Savannah is about an hour from Hilton Head Island by car and about 15-20 minutes by boat. I would definitely call ahead to make sure they can accommodate you
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