The track gauge adopted by the mainline railways of Ireland is 1600 mm (5 ft 3 in). This unusual gauge is otherwise found only in the Australian states of Victoria and South Australia (where it was introduced by the Irish railway engineer F. W. Shields), and in Brazil.
The first three railways had lines of three different gauges, the dimensions being : the Dublin and Kingstown Railway, 4 ft 8½ in (1435 mm); the Ulster Railway, 6 ft 2 in (1880 mm); and the Dublin and Drogheda Railway, 5 ft 2 in (1575 mm). The Board of Trade, recognising the chaos that would ensue asked one of their officers to advise. He consulted widely and eliminating the widest and narrowest gauges (Brunel's 7'0 1/4" and Stephenson's 4'8½"), all other answers lay between 5'0" and 5'6". By spliting the difference, a compromise Irish standard gauge of 5 ft 3 in (1600 mm) was reached. The gauge of the Ulster Railway was altered about 1846, and that of the Dublin and Kingstown Railway in 1857, the alteration costing the latter company £38,000.
Numerous narrow-gauge systems were built around Ireland, usually to a gauge of 3 feet (914 mm). Most are now closed, including what was the largest narrow-gauge system in Ireland or the U.K.: those operated by the County Donegal Railways Joint Committee. The Irish narrow gauge today survives as heritage railways in both the Republic and in Northern Ireland; and, in the Republic, in the bogs of the Midlands as part of Bord na Móna's peat transport network.
Bookmarks