The modernisation of the Caíde-Marco de Canaveses-Régua section makes it possible to provide the Douro Line with uniform characteristics in terms of rail operation, in particular by extending the electrified extension of the National Railway Network. The section has a total length of 57.8 km, with the assumption of allowing the extension of the suburban electric service, from Caíde to Marco de Canaveses and passenger services to Régua.