Roads in Portugal are defined by the Plano Rodoviário Nacional (PRN, ), which describes the existing and planned network of Portuguese roads. The present plan in force is the 2000 National Road Plan (PRN 2000), approved in 1998. It replaced PRN 1985, which itself had replaced PRN 1945.
The Portuguese road infrastructure was considered the best in Europe and the second best in the world by the World Economic Forum in its Global Competitiveness Report for 2014–2015.The Global Competitiveness Report 2014–2015, World Economic Forum, p. 429 In the 2017–2018 report, it was considered to 8th best in the world.The Global Competitiveness Report 2017–2018, World Economic Forum, p. 243 Nevertheless, all of these data were obtained through nothing more than an opinion survey of selected business executives.The Global Competitiveness Report 2017–2018, World Economic Forum, p. 333
The scenic road between Peso da Régua and Pinhão, in Trás-os-Montes region, was considered the world's best driving road, according to the Avis Driving Index.http://www.avisbestroad.com/ Avis Best Road This road is a section of the N 222 which follows the Douro Valley.
History of road classification in Portugal
First road plans
The first road plans in Portugal date back from 1843 and 1848, and were based on 18th century plans which prioritized connections between Lisbon and strategic points of the country, and as a support for fluvial routes. The planned network was classified in 1850 into estradas (roads) and caminhos (paths), with the estradas being classified as 1st and 2nd class. Caminhos were routes of merely local interest.
In 1862, the existing and planned roads were classified as 1st class roads or estradas reais (royal roads), 2nd class roads or estradas distritais (district roads), and estradas municipais (municipal roads). The estradas reais were those with direct or indirect (via railways, for instance) origin in Lisbon and were managed by the State. The estradas distritais were managed by the districts while estradas municipais were managed by the municipalities.
With the abolition of the monarchy in 1910, the estradas reais were renamed estradas nacionais (national roads).
In 1913, the Law of 22 February established a commission to study a new classification of the roads and propose guidelines to establish that classification. However, despite these efforts, many routes were not clearly classified and the condition of most roads was chaotic. Widespread use of the automobile in the 1920s created new pressure for reforming the Portuguese road network.
In 1926, under the Ditadura Nacional regime, a provisional General Plan of National Roads of 1st and 2nd class was established by Decree 12,100 of 31 July 1926, according to what was previewed by the Law of 22 February 1913. Both the 1st and 2nd class roads would be designated estradas nacionais, with the term estrada distrital disappearing. They were designated EN xx-x (for estradas nacionais followed by the number of the road and its class). This plan established 23 roads of 1st class (designated EN 1-1ª to EN 23-1ª) and 112 roads of 2nd class (designated EN 1-2ª to EN 112-2ª). The definite General Plan of National Roads was approved by Decree No. 16,075 of 30 September 1928. It kept the 23 1st class roads and the 112 2nd class ones, but some roads were rerouted, extended, or truncated.
The 1st class national roads included in the 1928 General Plan of National Roads were the following: Number Route Porto – Viana do Castelo – the margin of Minho river – São Gonçalo border Porto – Braga – Monção Viana do Castelo – Lindoso (border) Viana do Castelo – Braga – Bragança – Bridge over Maçãs river (border) Braga – Guimarães – Amarante – Vila Real – Bragança – França (border) Porto – Penafiel – Régua – Barca de Alva São Pedro do Sul – Vila Real – Chaves – border Aveiro – Viseu – Guarda – Almeida – Vilar Formoso (border) Buarcos – Figueira da Foz – Coimbra – Moncorvo – Podence Porto – Coimbra – Leiria – Caldas da Rainha – Loures – Lisbon Malveira – Ericeira – Sintra – Cascais – Algés (Lisbon) Lisbon – Santarém – Castelo Branco – Salvaterra do Extremo (border) Barreiro – Aldeia Galega – Almeirim – Barreiras do Tejo (Abrantes) Torres Novas – Abrantes – Proença-a-Nova Guarda – Castelo Branco – Portalegre Peniche – Santarém – Coruche – Évora Fronteira – Portalegre – Évora – Beja Aldeia Galega – Vendas Novas – Elvas – Bridge over Caia river (border) Cacilhas – Setúbal – Alcácer do Sal – Ferreira do Alentejo – São Brás de Alportel – Faro Alcácer do Sal – Grândola – Odemira – Lagos Sines – Ferreira do Alentejo – Moura – Rosal da Cristina (border) Odemira – Ourique – Mértola – Mina de São Domingos Lagos – Faro – Vila Real de Santo António
By Law No. 3,969 of 20 July 1927, the Junta Autónoma das Estradas (JAE, ) was created to study the condition of the Portuguese road network. The preliminary report was clear to state that from the of the planned national road network, were to be completed and from the already built, were in an almost-ruined condition.
In 1933, roads were reclassified as estradas nacionais (1st and 2nd class), estradas municipais and caminhos públicos (public paths), with the latter two under municipal management.
1945 National Road Plan
In 1933, the entire (i.e. built and planned) network of national roads totalled . The state recognized the importance of the road network and, in 1945, created the first real national road plan, the Plano Rodoviário Nacional de 1945 (PRN 45), defined in Law No. 34,593 of 11 May 1945. This plan comprised a national road network of .
PRN 1945 classified the national road network in Rede Fundamental (Fundamental Network) and Rede Complementar (Complementary Network). The latter served to support the fundamental network. Roads were classified according to the following:
Fundamental Network: Estradas nacionais (EN or N) 1st-class roads: Principal routes (itinerários principais): to Other first-class roads: to 2nd-class roads: to Complementary Network: Estradas nacionais (EN or N) 3rd-class roads: to . Branch roads, emerging from a determined road, which was identified by X, with a number of order according to point of origin, identified by Y. The road with most branch roads was , originally with 16 roads numbered to . (In 1961 and were renamed as and , respectively. However, later and were created, so N 1 resumed the record for 16 branches). These roads were planned to cover distances rarely longer than , closing some road grids, and connecting locations of some demographic importance which are not covered by the "parent" road such as less-important border crossings, railway stations, and seaports. There were 438 branch roads.
The National Roads Statutes were subsequently approved in 1949.Lei nº 2037 from August 19th, 1949 – Estatuto das Estradas Nacionais (en: National Roads' Statutes)
In 1961, separate legislation (Law No. 2110 of 19 August 1961)Lei nº 2110 August 19th, 1961 – Regulamento Geral das Estradas e Caminhos Municipais (en: General Regulation on Municipal Roads and Pathways) on municipal roads defined new guidelines on construction, maintenance, and commercialization of these roads, and those were classified as following:
Estradas municipais (EM or M):Decreto-Lei nº 42271 from May 20th, 1959 – Municipal Roads classification –, following a district sequence, so the sequence 501 and over was repeated in every district. Municipal Roads could have also Branch Roads, following the same rules as for National Roads Caminhos públicos or, from 1961, caminhos municipais (CM) and on, with the same numbering rules as Municipal Roads
The Main Roads could be, by law, upgraded to 4 lanes with central separation, if necessary. In fact this happened before PRN 1945, with the N7 motorway (now the A5) between Lisbon and the National Stadium completed in 1944, and in 1961 with the first of N1 motorway (now A1) between Lisbon and Vila Franca de Xira. The first urban highways were built in the 1960s. Nevertheless, most motorways built before 1985 had no number at all.
The road classes were distinguished using colour codes: red for first class, blue for second class, green for third class, yellow for municipal roads, and brown for municipal paths. These colours were applied as the basis of the location markers and occasionally in the background of the road numbers. The numbering distribution for main roads was according to the importance of its route in the network, and for N101 and over were numbered in a north-to-south fashion.
The length of the roads had no relation with its class (except for branch roads, which were usually short), with existing 3rd-class roads longer than , and main roads with as short as , like the N7 highway, now part of A5. The longest road of the 1945 Plan was N2, connecting Chaves to Faro, extending for .
According to PRN 1945, there were 18 Main Roads, designated N1 through N18.
Number Route Length Notes Lisbon – Vila Franca de Xira – Leiria – Pombal – Coimbra – Albergaria-a-Velha – Porto (northern end of upper deck of D. Luís Bridge) Originally about ; between Lisbon and the northern end of Av. da República in Vila Nova de Gaia On the 1945 National Roadway Plan, this was Portugal's main road, connecting Lisbon and Porto. Originally crossing the towns or city centres on its route, over the years many bypass roads have been built to avoid urban traffic.
In 1961, the new motorway section between Lisbon and Vila Franca de Xira, part of the future Lisbon–Porto motorway, was integrated into the N1. The original route became an extension of the N10. The N1 classification for the referred branch of A1 had been kept until 1985, thereafter the N1 road had its starting point at the level of km 26.
Also during the 1960s, a more direct and straight connection between Venda das Raparigas (Benedita, Alcobaça) and São Jorge (Porto de Mós) has been built. The original route was reclassified, in 1973, as N 8–6 (Venda das Raparigas–Alcobaça, or more properly Alcobaça–Venda das Raparigas) and N 8 (Alcobaça–vicinity of São Jorge), thus extending its route farther north.
According to PRN 1985, most parts of this road have been included on IC2, signed as IC2/N1. Some sections which aren't common with IC2 are intended for local traffic, or are parts parallel to auto-estrada sections of IC2. Chaves – Vila Real – Viseu – Penacova – Abrantes – Ponte de Sor – Montemor-o-Novo – Ferreira do Alentejo – Almodôvar – Faro The longest road of Portugal according to 1945 National Roadway Plan, connecting north to south, "cutting" the country halfway between west and east and crossing eleven of the eighteen districts of Portugal. In Trás-os-Montes and Viseu district N2 crossed district capitals (Vila Real and Viseu) and medium-sized cities (Chaves and Lamego) but south of that regions (i.e. roughly for the remaining 500 km), the road ran far from any major city until near its end in Faro. N2 never had an autonomous traffic that justified its importance in the 1945 Plan and the long national road became a sequential collection of regional sections. The failure of N2 proved that the major link between the Northern and Southern regions of Portugal should always cross Lisbon area (as happens nowadays with IP1 and IC1). In the 1985 and 2000 National Road Plans, IP3 (a single- or dual-carriageway highway) runs parallel to N2 in Trás-os-Montes and Viseu district, but south of that no major road follows the former N2 axis. Currently, almost all sections of N2 have been downgraded to regional or municipal roads.
The route classified as N2 by 1945 had been fully asphalted from the 1930s to 1944.
Many branches had been replaced in importance by the 1985 Plan's IP routes, some renamed as Estrada Regional (R 2), some were municipalized and some classified as historical patrimony.
Due to its characteristics, N2 is nicknamed Portuguese Route 66.