Thousand Islands – Frontenac Arch is one of four ecoregions of the Mixedwood Plains. The Thousand Islands in the Saint Lawrence River have a distinctive flora and fauna and are a part of the biological corridor. The bedrock is mostly gneiss, granite and marble, more than a billion years old. The Frontenac terrain is the youngest of the Ontario portions of the arch, dated at 1.2 billion years old. These rocks were once part of a large mountain chain of the ancient supercontinent of Rodinia. There is also a meteor crater near Holleford, where the shield meets the limestone plains of southeastern Ontario. The area
Ten Thousand Islands or families. Some of the Ten Thousand Islands are suitable for overnight visits, as dictated by the United States Fish and Wildlife Service. Since this is a wilderness area where wind, weather and lack of fresh water can become threatening, the Wildlife Service recommends only seasoned canoeists and sea kayakers attempt the trip. Part of the archipelago lies within Everglades National Park. The following islands are officially designated camping sites: Ten Thousand Islands archipelago is among the best and last remaining dark skies sites in the Southern Florida. Most notable is Pavilion Key that lies 11 miles south of Everglades