sentences:  It is linked by Interstate 95 and U.S. Route 1, which start in Miami and Key West, Florida, respectively, and terminate in Maine at the Canadian border, as well as the Northeast Corridor railway line, the busiest passenger rail line in the country that serves Amtrak and several commuter rail agencies.It is home to over 50 million people, and metropolitan statistical areas are contiguous from Washington to Boston.The region is not uniformly populated between the terminal cities, and there are regions nominally within the corridor yet located away from the main transit lines that have been bypassed by urbanization, such as Connecticut's Quiet Corner.