The Northeast Corridor is a major rail line in the United States that runs from Boston, Massachusetts, to Washington, D.C. It is the busiest passenger rail corridor in the country, serving millions of travelers each year. The corridor is primarily used by Amtrak, which operates high-speed trains like the Acela Express, as well as regional services. This rail line connects several key cities, including New York City and Philadelphia, making it an essential route for commuters and tourists alike. The Northeast Corridor is known for its efficiency and speed, significantly reducing travel time compared to driving or flying between these urban centers.