Jewell Island is a small island in Casco Bay, Maine, United States. About 1 mile (1.6 km) long from SW to NE, it is located off the coast of Cliff Island. It is a state-owned island with a small but protected harbor as well as camping and walking paths. There are also WWII towers on the island. Cocktail Cove is popular for kayaking and the Punchbowl located in the north east area of the island. The island is part of the city of Portland. Jewell Island can be reached by private boat or the Portland Express Water Taxi.
The island is rich in legend — tales are told of Captain Kidd cruising its coast and hiding treasure. The WWII bunkers are said to be haunted by soldiers, and the beaches by bootleggers. Several accounts of ghostly encounters can be heard in local towns.