Russ Dillingham/Sun Journal Visitors to the island enjoy a picnic lunch on the lawn as seen from the wrap-around porch of the Admiral Robert Peary home in Casco Bay off the coast of Harpswell. Russ Dillingham/Sun Journal EAGLE ISLAND — One of Maine’s lesser-known state parks is the island home of Admiral Robert Peary, who in 1909, with five men and sled dogs, is credited with an expedition to the North Pole. Eagle Island, a National Historic Landmark, “is a place that Peary and his family called their promised land,” reads a National Park Service plaque on the island. The National Park Service says the island “possesses national significance commemorating the history of the United States” and calls Peary America’s foremost arctic explorer.