Shell Island Snorkeling Packages offer the chance to experience tropical fish, corals and sponges. Swim with our local, friendly dolphins that regularly frolic along the shores of Shell Island. Fun for beginners and pros of all ages! Snorkeling at Shell Island or at St. Andrews State Park is one of the most popular things to do. There is no better way to get up close and personal with the marine life than actually swimming with them and exploring their natural habitat. Here at St. Andrews State Park we offer snorkeling packages for the whole family.