Northeast megalopolis includes cities.
Boston ( pronounced [ ˈbɒstən ] ) is the capital and most populous city of the Commonwealth of Massachusetts in the United States . The Northeast megalopolis ( also Boston -- Washington Corridor or Bos-Wash Corridor ) is the most heavily urbanized region of the United States , running primarily northeast to southwest from the northern suburbs of Boston , Massachusetts , to the southern suburbs of Washington , D.C. , in Northern Virginia .