Regional road

A regional road (Irish: bóthar réigiúnach) in Ireland is a class of road not forming a major route (such as a national primary road or national secondary road), but nevertheless forming a link in the national route network. There are over 11,600 kilometres of regional roads. Regional roads are numbered with three-digit route numbers, prefixed by "R" (e.g. R105).

Until 1977, classified roads in Ireland were designated with one of two prefixes: "T" for Trunk Roads and "L" for Link Roads. The Local Government (Roads and Motorways) Act authorised the designation of roads as National roads: in 1977, twenty-five National Primary roads (N1-N25) and thirty-three National Secondary roads (N51-N83) were initially designated under Statutory Instrument S.I. No. 164/1977.

Many of the remaining classified roads became Regional roads (formally authorised under the Roads Act 1993, having been indicated as such on road signs on a non-statutory basis for some years previously) and their routes were designated under a Statutory Instrument ('SI') in 1994. The latest SI designating the routes of Regional roads was published in 2012: the Roads Act 1993 (Classification of Regional Roads) Order 2012.

Other roads formerly classified as Trunk or Link roads eventually became Local roads.

Older signs showing the former Trunk and Link road designations are still to be seen in some locations. The L (for Link Road) prefix on these signs is not connected to the network of Local roads currently in place.

Unlike national roads, regional roads are maintained by local county or city councils rather than the National Roads Authority. The vast majority of the regional road network is made up of single-carriageway roads although some roads are dual-carriageway (see: High-capacity regional roads below). Until the late 1990s, such roads were often in a very poor condition, although increased road maintenance funding to local councils has resulted in more frequent resurfacing of regional roads, as well as relaying and realignment on some routes.

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