Utila is the smallest of Honduras' major Bay Islands, after Roatán and Guanaja, in a region that marks the south end of the Mesoamerican …Utila is the smallest of Honduras' major Bay Islands, after Roatán and Guanaja, in a region that marks the south end of the Mesoamerican Barrier Reef System, the second-largest in the world. It has been documented in history since Columbus' fourth voyage.