During and after the American Civil War, the first transcontinental railroad was built, to join California with the rest of the national network, at a connection in Iowa.

Freight railroads invested in modernization and greater capacity as they entered the 21st century, and intermodal transport continued to grow, while traditional traffic, such as coal, fell.

There, the main competition came from canals, many of which operated under state ownership and from privately owned steamboats plying the nation's vast river system.

More than one in ten of the then 1,058 graduates from the U.S. Military Academy at West Point between 1802 and 1866 became corporate presidents, chief engineers, treasurers, superintendents and general managers of railroad companies.

[4] Among the Army officers who thus assisted the building and managing of the first American railroads were Stephen Harriman Long, George Washington Whistler, and Herman Haupt.

In 1843, renamed the Summit Hill & Mauch Chunk Railroad, it added a steam powered cable-return track for true two-way operation and ran as a common carrier and tourist road from the 1890s to 1937.

The C&A ran successfully for decades connecting New York City to the Delaware Valley, and would eventually become part of the Pennsylvania Railroad.

Large railroad companies, including the New York Central, Grand Trunk Railway, and the Southern Pacific, spanned several states.

In response to monopolistic practices, such as price fixing and other excesses of some railroads and their owners, Congress created the Interstate Commerce Commission (ICC) in 1887.

However it was not the world's longest railroad, as Canada's Grand Trunk Railway (GTR) had, by 1867, already accumulated more than 2,055 kilometres (1,277 mi) of track by connecting Portland, Maine, and the three northern New England states with the Canadian Atlantic provinces, and west as far as Port Huron, Michigan, through Sarnia, Ontario.

Authorized by the Pacific Railway Act of 1862 and heavily backed by the federal government, the first transcontinental railroad was the culmination of a decades-long movement to build such a line and was one of the crowning achievements of the presidency of Abraham Lincoln, completed five years after his death.

The standard historical interpretation holds that the railroads were central to the development of a national market in the United States and served as a model of how to organize, finance and manage a large corporation,[10] along with allowing growth of the American population outside of the eastern regions.

The major railroads passenger flagship services included multi-day journeys on luxury trains resembling hotels, which were unable to compete with airlines in the 1950s.

Overregulation, management and unions formed an "iron triangle" of stagnation, frustrating the efforts of leaders such as the New York Central's Alfred E. Perlman.

The proponents were aided by the fact that few in the federal government wanted to be held responsible for the seemingly inevitable extinction of the passenger train, which most regarded as tantamount to political suicide.

The urgent need to solve the passenger train disaster was heightened by the bankruptcy filing of the Penn Central, the dominant railroad in the Northeastern United States, on June 21, 1970.

The act was an attempt to salvage viable freight operations from the bankrupt Penn Central and other lines in the northeast, mid-Atlantic and Midwestern regions.

[22] U.S. freight railroads are separated into three classes, set by the Surface Transportation Board, based on annual revenues: In 2013, the U.S. moved more oil out of North Dakota by rail than by the Trans-Alaska pipeline.

Privately run inter-city passenger rail operations have also been restarted since 2018 in south Florida, with additional routes under development.

[32] In addition, the Texas Central Railway is currently developing plans for a proposed greenfield high-speed rail line using Japanese Shinkansen trains between Dallas and Houston.

[34] A proposal is in the works for a over 200mph high-speed rail system from Dallas/Fort Worth to Atlanta, Georgia along the I-20 corridor, currently named the I-20X, that will pass directly through places like Kilgore, Texas a historic railway city, bringing passenger rail service to that corridor for the first time since the Texas and Pacific's unnamed successor to the Louisiana Eagle in the late 1960s.

[35][36]This initiative promises to support regional development, reduce car dependency, and create jobs in areas like Kilgore, Tyler and East Texas.

The roomette featured a large picture window, a privacy door, a single fold-away bed, a sink and small toilet.

The steering axles evolved into mechanisms that would also tilt the passenger car as it entered a curve to counter the centrifugal force experienced by the train, further increasing speeds on existing track.

Talgo's trains are used on some short and medium distance routes such as Amtrak Cascades from Eugene, Oregon, to Vancouver, British Columbia.

[38] As of 2022, the only operating high speed rail service in the United States is Amtrak's Acela, between Washington, DC, and Boston.

Despite commuter trains also running along the Northeast Corridor alongside Amtrak services on the route, only one commuter rail line can have similar speed ranges to higher-speed rail, which is the MARC Penn Line that runs from Washington, D.C. to Baltimore, MD, which can reach up to speeds of 125 miles per hour (201 km/h).

A proposal is in the works for a over 200mph high-speed rail system from Dallas/Fort Worth to Atlanta, Georgia along the I-20 corridor, currently named the I-20X, that will pass directly through places like Kilgore, Texas a historic railway city, bringing passenger rail service to that corridor for the first time since the Texas and Pacific's unnamed successor to the Louisiana Eagle in the late 1960s.

[39][40]This initiative promises to support regional development, reduce car dependency, and create jobs in areas like Kilgore, Tyler and East Texas.

[41] Every piece of railroad rolling stock operating in North American interchange service is required to carry a standardized set of reporting marks.