5 ft 3 in gauge railways

Railways with a track gauge of  fall within the category of broad gauge railways. , they were extant in Australia, Brazil and on the island of Ireland.

History

 * 600 BC
 * The Diolkos (Δίολκος) across the Isthmus of Corinth in Greece – a grooved paved trackway – was constructed with an average gauge of.
 * 1840
 * The Grand Duchy of Baden State Railway was constructed in 1840–1851 to gauge before being converted to  in 1854–1855.


 * 1843
 * The Board of Trade of the United Kingdom of Great Britain and Ireland, after investigating a dispute caused by diverse gauges, recommended the use of in Ireland.


 * 1846
 * The Regulating the Gauge of Railways Act 1846 made mandatory throughout all of Ireland.


 * 1847
 * The Swiss Northern Railway was opened as a line and converted to  in 1854.


 * 1854
 * The first Australian railway to operate steam-powered freight and passenger services, Melbourne and Hobson's Bay Railway Company, was built as a line.


 * 1858
 * The first Brazilian railway was opened: the Companhia de Estrada de Ferro Dom Pedro II.


 * 1863
 * The Canterbury Railway in New Zealand was built in . It was converted to in 1876.

Nomenclature

 * In Great Britain and Ireland, the gauge is known as Irish gauge.  In Ireland it is also common to hear it referred to as "standard gauge" or "broad gauge" when distinguishing it from the various 3 ft (narrow gauge) railways of the island.
 * In Australia, where the states of Victoria and South Australia have this gauge (as did Tasmania in the 19th century), it is also known as broad gauge.
 * In Brazil, the gauge is mainly known as broad gauge (bitola larga), but occasionally as Irish gauge (bitola irlandesa).

Similar gauges
The Pennsylvania trolley gauges of and  are similar to this gauge, but incompatible. There is also a SEPTA subway–surface trolley lines gauge. See: Track gauge in Ireland.

Locomotives
Before the advent of diesel and electric traction, one of the advantages of the broader Irish gauge compared to  was that more space between steam locomotive frames allows for a bigger firebox, enabling generation of more steam.