Washington, D.C. is in the Northeast megalopolis.
The Northeast megalopolis -LRB- also Boston -- Washington Corridor or Bos-Wash Corridor -RRB- 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 .	Boston	Boston	urbanized region	Urban area	United States	United States	suburbs	suburbs	Massachusetts	Massachusetts	Northern Virginia	Northern Virginia	megalopolis	Megalopolis (city type)
