Trunk roads in Ireland

Ireland has an extensive network of public roads which connect all parts of the country with each other. Roads in Ireland are currently classified as motorways, National Primary routes, National secondary routes, Regional roads and Local roads. The introduction of this classification system began in 1977.

Prior to this, the Republic of Ireland had a different road classification and numbering system. Roads fell into three categories: T (Trunk Roads), L (Link Roads) and unclassified roads. The origins of this system lie in pre-independence legislation: the preliminary section of Statutory Instrument S.I. No. 55/1926 — Road Signs and Traffic Signals Regulations, 1926 states that the Ministry of Transport Act, 1919 gave the Minister for Local Government and Public Health the power to assign a "route letter and number" to a road, while Section 6.4 of Part I of the Regulations specifies the positioning of the "route letter and the number of the road" on directional signs. A reference in the Statutory Instrument to the "classification of roads as a 'Trunk' or 'Link' Road" indicates that a system of route classification and numbering was envisaged in the 1920s. However, at present, there is no information about when the Trunk and Link road-numbering system was actually introduced on signposts. Even though legal authority for the erection of directional signposts was given to local councils, the Automobile Association of Ireland began an extensive road signposting scheme in 1938 which included comprehensive signposting of routes from Belfast, Cork and Dublin.

Evidence that the Trunk Road and Link Road classification and numbering system had been well established by the 1950s is found in Statutory Instrument S.I. No. 284/1956 — Traffic Signs Regulations, 1956 which contains examples of several directional signs. The first and second examples show the T8 as the route to Wexford and Rosslare. In addition, Esso road-maps of Ireland from the 1950s show the Trunk and Link road network. Despite its long-standing use, the original Trunk and Link road system was never legislated for and the routes of Trunk Roads and Link Roads were never formally designated by law.

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