The Mingan Archipelago consists of a coastal chain of 900 islands and islets in the Gulf of St. Lawrence, stretching over a distance of 150 km. The most striking features of the islands are their dramatic topography and rocky shorelines. For generations, lighthouse keepers have kept watch and guided ships through the often treacherous waterway. The Mingan has Canada's largest concentration of shoreline arches and grottoes as well as the immense limestone sculptures known as "monoliths". The combination of climate and latitude make the islands the ideal habitat for rare, arctic, alpine plants. Over 200 species of birds can be seen on the islands, but the most endearing is the Atlantic Puffin.