Cliff Island is an island in Casco Bay Maine. It is part of the city of Portland, Maine. As of the 2000 census, the island had a year-round population of approximately 60 people. In the summer, the island’s population grows to about 200, despite the fact that it is the only year-round inhabited island in Casco Bay with no paved roads. Originally named Crotch Island for its H-shape and natural harbors, the name was changed to end mail mix-ups with several other “Crotch Island”s in Maine.