DYNAMAP is a LIFE+ project aimed at developing a dynamic noise mapping system able to detect and represent in real time the acoustic impact of road infrastructure. The main objective of this project is to ease and reduce the cost of periodically updating noise maps, as required by the European Directive 2002/49/EC on environmental noise. To that end, an automatic monitoring system, based on customised low-cost sensors and a software tool implemented on a general purpose GIS platform, will be developed and built in two pilot areas located along the A90 motorway that surrounds the city of Rome (Italy), and inside the agglomeration of Milan (Italy). A one-year survey will then be undertaken to check the reliability, effectiveness and efficiency of the DYNAMAP system.