Maine State Ferry Service: Rockland, Vinalhaven, Bass Harbor and six other ports. Casco Bay Lines: Portland (Maine), Peaks Island, Little Diamond Island, Great Diamond Island, Long Island (Maine), Chebeague Island, Diamond Cove and Cliff Island. Downeast Windjammer Cruise Lines: Bar Harbor, Winter Harbor, Great Cranberry Island, Islesford, Northeast Harbor, Southwest Harbor, Eastport and Lubec. Balmy Days Cruises: Boothbay Harbor, Squirrel Island, Monhegan and Burnt Island. Isle au Haut Boat Services: Stonington, Isle au Haut, Duck Harbor and Seal Island. Monhegan Boat Line: Port Clyde, Monhegan and Eastern Egg Rock. Beal & Bunker: Great Cranberry Island, Islesford and Northeast Harbor. Bay Ferries: from Yarmouth (Nova Scotia). And one other company.