What Is a High-Speed Rail System? Definition, Meaning and Concept

High-speed rail systems are trains that operate at significantly higher speeds than normal trains, although the exact definition of speed varies between experts and agencies. Found in many urban areas, high-speed rail offers passengers a quick and efficient alternative to other modes of public transportation. Although extremely popular in Europe and parts of Asia, high-speed rail is notably absent in most of the United States, due to the overwhelming preference for personal transportation using automobiles.

Governing and authorizing bodies offer different definitions of what constitutes a high-speed rail system. Rail authorities in the European Union limit the term to trains regularly traveling at speeds of more than 125 miles per hour (200 kilometers per hour), although the limit is higher for trains built on newer tracks. In the United States, high-speed trains must travel faster than 90 mph (145 kph) to be classified as high-speed.

High-speed rail was developed in the mid-20th century, gaining considerable popularity after the end of World War II. Japan was one of the first countries to incorporate high-speed rail into its public transportation system. Shinkansen, or the bullet train, opened in 1964 as a service between the Tokyo and Osaka metropolitan areas. Since then, the railway has been a model of fast, safe and efficient travel that extends through most of the country.

As with any speed-based technology, it's only natural that experiments continually test how fast trains can travel. Using the newest technology, Japan currently holds the world speed record, at 361 mph (581 kph). The train that reached this speed, the MLX01, works primarily through magnetic levitation technology. This new method of moving trains, often called a maglev, uses magnets to pull the train at blinding speeds thanks to reduced friction. Although few maglev trains currently operate, Japan plans to safely implement the technology throughout its high-speed rail system by 2025.

As environmental concerns rise in the wake of global warming, high-speed rail has gained renewed interest in the 21st century. The United States, a country that has typically eschewed railroads in favor of ever-larger highways and new car technology, has begun plans to build several high-speed systems in different states. Following the example of the successful Acela line linking New York City and Washington, DC, voters have approved plans and budgets for similar high-speed rail lines in California. Commissions in Texas and Chicago are also involved in studies of the potential benefits of new high-speed lines.