The first railroad of sorts, called a tramroad -- built in 1764 for the military -- was in New York. Many years later, in 1826, a commercial tramroad was built in Massachusetts. In 1826, John Stevens introduced steam locomotion and four years later construction began on the Baltimore and Ohio railway.
According to The National Railroad Construction and Maintenance Organization, the organization formed in the early 1970s so unionized contractors could bargain with labor workers to form a national agreement. That agreement, signed by 20 American railroad construction companies, is The Rail Transportation and Operations Agreement. It guides companies in railway construction.
Railroad construction still takes place as new railroad stations are built and tracks are updated. The railroad industry employs thousands of people throughout the United States through companies such as Amtrak, Union Pacific and Norfolk Southern.