By air. Portland International Jetport (PWM), three miles southwest of downtown, has direct flights from major East Coast cities (New York, Washington, Philadelphia) and seasonal service further afield. Public bus 5 connects the airport to the Old Port in about twenty minutes for under three dollars.
By bus. Concord Coach Lines and Greyhound run multiple daily services from Boston (around two hours) and points south. The terminal is on Thompson's Point, a few minutes from downtown by taxi or bus 8.
By train. The Amtrak Downeaster connects Portland with Boston (just over two hours) and continues north to Brunswick. The Portland Transportation Center on Thompson's Point handles both train and bus arrivals; a free shuttle runs into the Old Port.
By car. I-95 (Maine Turnpike) is the main highway approach. From Boston, expect two hours. Downtown street parking is metered and tight; large garages on Spring and Fore Streets are easier in summer.