Bar Harbor is a town on Mount Desert Island in Hancock County, Maine, United States. As of the 2010 census, its population is 5,235. Bar Harbor is a famous summer colony in the Down East region of Maine. It is home to the College of the Atlantic, Jackson Laboratory and Mount Desert Island Biological Laboratory (Salisbury Cove village). Bar Harbor is home to the largest parts of Acadia National Park, including Cadillac Mountain, the highest point within 25 miles (40 km) of the coastline of the Eastern United States, and, offshore, the Porcupine Islands.