This article is based on the PIARC Special Project “Smart Roads Classification” which was funded by PIARC with financial support from Spain, Belgium, Canada-Québec and the USA. The project was carried out by a team from the Universitat Politècnica de València (UPV, Spain) with the support of PIARC General Secretariat and of an Oversight Team from different countries. The full Report can be found in the special projects section of PIARC’s website;