Already regarded as one of the top destinations for tourists in the South and the U.S., Savannah is about to embark on a new chapter when a flotilla of sail pays a call. The city will host the start of the Tall Ships Challenge, which begins May 3, and is an annual event that rotates between the Atlantic coast, the Pacific coast and the Great Lakes. “That’s going to be a terrific event for our community,” said Joe Marinelli, president of Visit Savannah, the Savannah Chamber of Commerce’s tourism arm.