staying safe
In keeping with Maine's reputation as a relatively crime-free U.S. State, there is no place in Portland a visitor should feel like they shouldn't visit during the day. As in any city, be alert in areas that are not well lit at night or deserted. Act with common sense and you should have no trouble.
Maine state liquor laws require all bars to close promptly at 1 am. The Old Port's numerous bars empty into the street at this time. Some rowdiness is to be expected, but there is always an increased police presence on busy nights.