Lake Superior covers 31,700 square miles and holds as much water as Lakes Michigan, Huron, Erie and Ontario combined, with room left over for three extra Lake Eries. It also holds many national treasures like the Apostle Islands and many state parks and recreational areas. The pristine waters and picturesque landscapes draw tourists from all over the world to enjoy the many outdoor recreation and scenic opportunities. Lake Superior also support diverse aquatic and near–shore habitats. Sandy beaches, rocky shorelines, wetlands and the world's largest freshwater dune system can all be found here. Each of these habitats and their collection of plants is unique. Some are found nowhere else on Earth.