Northeast megalopolis

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Northeast megalopolis
Megaregion of the United States
Major cities of the Northeast megalopolis (from top to bottom): Boston, New York City, Philadelphia, Baltimore, and Washington, D.C.
Nickname(s):  Northeast corridor, BosWash, Boston–Washington corridor, Eastern Seaboard,[1] Atlantic Seaboard
Interactive map of the Northeast megalopolis Core combined statistical areas (CSAs)   Boston–Worcester–Providence, MA–RI–NH   New Haven–Hartford–Waterbury, CT CSA   New York–Newark, NY–NJ–CT–PA CSA   Philadelphia–Camden–Wilmington, PA–NJ–DE–MD   Washington–Baltimore, DC–VA–MD–WV–PA Outlying metropolitan areas   Allentown–Bethlehem, PA–NJ CSA   Scranton–Wilkes-Barre, PA MSA   Harrisburg–York–Lebanon, PA CSA   Lancaster, PA MSA   Portland–Lewiston, ME CSA   Springfield, MA CSA   Salisbury, MD CSA and Seaford, DE MSA   Richmond, VA MSA   Virginia Beach–Norfolk, VA–NC CSA   Non-metropolitan counties in the megaregion
Federal districts	Washington, D.C.
Largest city	New York City (8,804,190)
Area
• Total	56,200 sq mi (146,000 km2)
Population  (2022[2])
• Total	50,244,897
• Density	894/sq mi (345/km2)
GDP [3]
• Total	$5.229 trillion (2022)[4]
• Per capita	$104,106 (2022)

The Northeast megalopolis, also known as the Northeast Corridor, Acela Corridor,^[5] Boston–Washington corridor, BosWash, or BosNYWash,^[6] is the most populous megalopolis exclusively within the United States, with slightly over 50 million residents as of 2022. The nickname "BosWash" for the region was first named by futurist Herman Kahn in a 1967 essay.^[7] It is the world's largest megalopolis by economic output.^[8]

Located primarily on the Atlantic Coast in the Northeastern United States, the Northeast megalopolis extends from the northern suburbs of Boston to Washington, D.C., running roughly southwesterly along a section of U.S. Route 1, Interstate 95, and the Northeast Corridor train line.^[9] It is sometimes defined more broadly to include other urban regions, including the Richmond and Hampton Roads regions to the south; Portland, Maine, and Manchester, New Hampshire, to the north; and Harrisburg, Pennsylvania, to the west.^[10]

The region includes many of the nation's most populated metropolitan areas, including those of New York City, Philadelphia, Washington, D.C., Boston and Baltimore.^[11] As of 2020, it contained more than 50 million people, about 17% of the U.S. population on less than 2% of the nation's land area, with a population density of about 1,000 people per square mile (390 people/km²), far more than the U.S. average of 80.5 per square mile^[12] (31 people/km²). At least one projection estimates the area will grow to 58.1 million people by 2025.^[13]

Before the term "Megalopolis" became widely used, Walter Hedden identified the growing interdependence of large cities in the Northeast in his 1929 book, specifically regarding the sourcing of milk. ^[14] French geographer Jean Gottmann Then popularized the term "megalopolis" in his 1961 study of the region, Megalopolis: The Urbanized Northeastern Seaboard of the United States. Gottmann concluded that the region's cities, while discrete and independent, are uniquely tied to each other through the intermeshing of their suburban zones, taking on some characteristics of a single, massive city: a megalopolis, a term he co-opted from an ancient Greek town of the same name that named itself out of aspirations to become the largest Greek city.