The Porcupine Islands, named for their resemblance to a group of porcupines, in Frenchman Bay off the coast of Bar Harbor. The islands are Sheep Porcupine Island, Burnt Porcupine Island, Long Porcupine Island and Bald Porcupine Island.
The islands are uninhabited and owned by Acadia National Park. They are nesting areas for a number of sea birds and access to some islands is restricted during nesting season.
The islands get their distinctive shape from their formation as they were carved by retreating glaciers moving north to south. This created the gentle slope on the north side with a sharp drop off in the south end.
