Auto-estrada

Roads in Portugal are defined by National Road Plan, 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 has replaced the previous PRN 1985, which itself had replaced the 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 scenic road between Peso da Régua and Pinhão, in Northern Portugal, was considered the World Best Driving Road, accordingly to the Avis Driving Index. This road is a section of the N 222 which route follows the Douro Valley.

The first real projects for road plans in Portugal date back from 1843 and 1848, and were based on 18th century plans which was based on connections between Lisbon and strategical points of the country, and as a support for fluvial routes. The precognized network was classified in 1850 as estradas (roads) and caminhos (paths), with the estradas being classified as 1st and 2nd class. Caminhos were routes of mere local interest.

In 1862, the roads (existing and projected) 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 the estradas municipais were those 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 establishes a commission to study the new classification of the roads and presents the guidelines to proceed to that classification. However, The new classification and road plan would only be established 13 years later.

Despite these efforts of a constitution of a road network, many routes were not clearly classified and the state of most roads was chaotic, and with the expansion of the automobile in the 1920s, new directions should be taken upon the Portuguese road network.

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Wikipedia