A mixed-gauge railway provides for more than two separate gauges, but is also a term sometimes used to denote dual-gauge.

In Indian English, bogie may also refer to an entire railway carriage. A dual-gauge railway is a line of track that provides for trains of two separate gauges. There will be two vital rails ("gauge" rails), one for each gauge close together and a third rail, a "common" rail further away. A dual gauge railway is a track that allows the passage of trains of two different track gauges.It is sometimes called a "mixed gauge" track. A bogie in the UK, or a railroad truck, wheel truck, or simply truck in North America, is a structure underneath a railway vehicle (wagon, coach or locomotive) to which axles (and, hence, wheels) are attached through bearings.In Indian English, bogie may also refer to an entire railway carriage.

A dual gauge track consists of three rails. A dual gauge railway is a track that allows the passage of trains of two different track gauges. A dual gauge track consists of three rails.

Video explaining the variable gauge system Talgo RD (English 2008) There will be two vital rails ("gauge" rails), one for each gauge close together and a third rail, a "common" rail further away. A bogie in the UK, or a railroad truck, wheel truck, or simply truck in North America, is a structure underneath a railway vehicle (wagon, coach or locomotive) to which axles (and, hence, wheels) are attached through bearings. A total of 58 dual-gauge bogies is being supplied by Alstom from a factory in Germany. The gauge-changing system devised and developed by Prose adapts the height of the cars to match platform heights — there is a difference of 180 mm. It is sometimes called a "mixed gauge" track.