The term “high rail” is used in several different ways in railroading contexts in reference to several different styles of tracks and railroad equipment. Additionally, it refers to a specific type of model railroading. The type of high rail under discussion is usually clear from the context.
Some people use this term to refer to high speed rail. High speed rail, primarily used for passenger transport, runs on dedicated tracks which allow trains to reach very high speeds. High speed rail systems can be seen operating in several nations around the world, and in many regions they are extremely popular for public transit and tourists alike. These high speed trains can get people between locations in a fraction of the time it would take a car to travel the same distance, and they are more suitable for travel over relatively short distances than aircraft.
People may also refer to elevated rail as high rail. Elevated rail tracks are used by some rail authorities to create dedicated tracks when limited space is available. By running the trains above the roadway, operators can run the trains without having to stop for traffic. A classic example of this type of high rail is Chicago's L or El rapid transit system.
In the world of model railroading, high rail or high railing is an approach which involves the use of equipment from manufacturers which has a history of being not quite to scale. High rail is often associated with Lionel products, which classically had tracks which were higher than they should be for the scale to be accurate. High railers or hirailers as they are also known have a variety of approaches to their work, with some aiming for a high level of detail and realism, while others simply enjoy running model trains, with less of an attention to detail. High rail enthusiasts will also argue briskly about what, exactly, “high rail” is.
The related term hi-rail or hirail used in full-scale railroading should not be confused with hirailing. “Hi-rail” refers to railroad equipment which can run both on the highway and on the railroad tracks. This type of equipment is often used for track maintenance and inspections, as it is highly flexible and allows operators to use it in a variety of ways. Some amateur train enthusiasts also maintain hi-rail equipment and may be allowed to travel on railroad tracks by special arrangement with the railroad, usually in the form of a group with other enthusiasts.