High Quality Content by WIKIPEDIA articles! Fort De Soto Park is located just outside the city of St. Petersburg, Florida. This park, operated by Pinellas County, is made up from five offshore keys, or islands lying to the city`s south-southwest: Madelaine Key, St. Jean Key, St. Christopher Key, Bonne Fortune Key and the main island, Mullet Key. Today all are connected by land to each other. The island group is accessible by toll road from the mainland.