Lebar sepur ganda
caption: Penambat rel pada track pengukur ganda yang menunjukkan celah minimum yang dapat dipraktikkan antara dasar dua rel – sekitar 40 mm (11/2 in.) – yang menentukan kemungkinan perbedaan minimum pada pengukur dalam konfigurasi tiga rel.
caption: Konfigurasi track pengukur ganda (1600 mm dan 1435 mm).
caption: Penataan empat rel pengukur standar dan meteran di Chemin de Fer de la Baie de Somme . Perbedaan pengukur sebesar 435 mm juga dapat diakomodasi dalam konfigurasi tiga rel.
caption: Cross-section of triple-gauge track at Gladstone and Peterborough , South Australia , before gauge standardisation . The three gauges require the respective gaps between the outer and inner rails to be different, unlike four-rail dual gauge.
caption: The Gorton Foundry of Beyer, Peacock and Company was typical of locomotive and rolling stock manufacturers that exported to many countries. This track of four gauges traversed two turntables, requiring the rails to be centralised.
caption: Rollbocks compared to transporter wagons
caption: Standardised containers have revolutionised rail, road and sea freight transport . Although mechanisation has speeded up handling, moving containers from one train to another because of different rail gauges is costly and inefficient.