Northeast megalopolis

About

The Northeast megalopolis, also known as the Northeast Corridor, Acela Corridor, Boston–Washington corridor, BosWash, Bos–Wash corridor or BosNYWash, is the most populous megalopolis exclusively within the United States, with slightly over 53 million residents as of 2024. The nickname "BosWash" for the region was first used by futurist Herman Kahn in a 1967 essay. It is the world's largest megalopolis by economic output.

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. 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. The coastal waters of the Northeast megalopolis constitute one of the fastest-warming urban ocean shorelines in the world.