High Quality Content by WIKIPEDIA articles! The Plano Rodoviário Nacional (National Roadway Plan; PRN 2000) describes the existing and planned network of roads in Portugal. There are two types of routes in the plan: itinerários principais (IP; principal/main routes) and itinerários complementares (IC; complementary/secondary routes). Either type of route may be composed of several motorway/freeway/expressway type roads (i.e., grade-separated, controlled access roads, called auto-estradas in Portuguese) or regular roads (i.e., at-grade, non-controlled access roads) or a combination. Many roads will have more than one number simultaneously. Auto-Estradas are roads which meet certain specifications. These roads are equivalent to motorways in many English-speaking countries and to expressways or freeways in the United States. Each Auto-Estradas forms part or all of an IP or an IC. These are dedignated with an "A" code as well as an IP or an IC code, though they are typically known tomotorists by the "A" designation. In addition, many of these roads are part of the European road network, and so also carry an "E" designation, which may serve as reference for non-Portuguese drivers.