The NRSO campaign for the promotion of city-wide 30km/h speed limit in all cities by running 30 Marathons in 30 months by Prof. George Yannis has received wide publicity in the tv, the radio, newspapers, magazines and the social media, as well as in scientific journals, conferences and workshops, with the active support of the NTUA and several International Organisations (ETSC, ECTRI, UITP, PolisERF, IRF, FERSI, FEHRL, ECF, Walk21). This campaign has a particularly significant social impact, as depicted by international findings, demonstrating an average 37% reduction in fatalities in road crashes in cities which have adopted the 30km/h speed limit, together with significant environmental, energy and health benefits. All these media interventions are available at: