itinerário complementar

The class of road in the national road network that ranks below the itinerário principal. Under the PRN 2000 road plan (Decreto-Lei n.º 222/98), together with the estradas nacionais it makes up the "complementary network": it links the country's main routes with towns of district and inter-municipal importance, and also includes the main ring roads and access roads around Lisbon and Porto. It is marked with the letters IC and a number, such as IC2 or IC17. The plan includes 34 such routes, and Infraestruturas de Portugal directly manages 1,809 km of roads in this class, compared with 464 km of itinerário principal.