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. These largely correspond to modern N and R roads in Ireland

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^[1] 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. The Statutory Instrument refer to the "classification of roads as a 'Trunk' or 'Link' Road".

In early 1926 the Minister made a Main Road Order which came into legal effect on 1 April 1926. The contents of this proposed order were communicated to local authorities in advance.,^[2] this initial Main Road Order established the initial T Road and L Road networks in each county in 1926 and required county councils to maintain these main roads.

A reply to a question in parliament, given in 1964, described the Main Road Order process.^[3]

"Subsequently, in the period 1925–26, a further classification of roads was made pursuant to the Local Government Act, 1925, into main, county and urban roads, for the purpose of apportioning statutory responsibility for construction and maintenance, and for determining the chargeability of roads expenses for the purposes of annual estimates. The 1925 Act classification, like the 1919 Act classification, was also made after consultation with the local authorities, and the roads which were declared to be main roads were the trunk and link roads of the 1919 Act classification together with some additional roads decided upon after the consultation which I have mentioned."

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.^[4]

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.^[5]

This current system of road classification and numbering has its origins in the late 1960s: the Minister for Local Government, Kevin Boland, announced on 23 July 1969 that a national road network would be formed.^[6] In 1974, the Local Government (Roads and Motorways) Act came into effect. It allowed for designation of roads as motorways or national roads. National roads were first designated by Statutory Instrument S.I. No. 164/1977 on 1 June 1977. Twenty-five National Primary routes (N1-N25) and thirty-three National Secondary routes (N51-N83) were initially designated.

The changeover to the new system was gradual: a route planning map of Ireland from the late 1970s (or early 1980s), divided into a northern section and a southern section, shows a mixture of Trunk Road, Link Road and National route numbers.