Texas gauge

5 ft 6 in/​1,676 mm is the size of a broad track gauge commonly used in India, Pakistan, west of Bangladesh, Sri Lanka, Argentina, Chile, and on the BART (Bay Area Rapid Transit) in the San Francisco Bay Area. In South Asia it is simply known as "Broad gauge", while in North America, it is called Provincial, Portland, or Texas gauge. Elsewhere it is known as "Indian gauge". It is the widest gauge in regular passenger use anywhere in the world.

In British India, some standard gauge freight railways were built in initial period, though they were dismantled later. Later, in 1850s, the gauge of 1,676 mm (5 ft 6 in) was adopted as standard for the nation-wide network.

Rail transport in India today is predominantly on 1,676 mm (5 ft 6 in) broad gauge barring heritage railways. Small stretches of the network use metre and narrow gauges. Urban rail is mostly on standard gauge, although some initial lines use 1,676 mm (5 ft 6 in) broad gauge.

Bangladesh Railways uses a mix of 1,676 mm (5 ft 6 in) broad gauge and metre gauge. The broad gauge network is primarily located to the west of the Jamuna River, while the metre gauge network is primarily located to its east. The Jamuna Bridge is a mixed use bridge that contains a dual gauge connection across the river linking both networks.

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