In Italy, in 1960, Bruno Touschek conceived and built the first particle-antiparticle collider, called AdA. The different roads and pathways which led to the successful demonstration that it was possible to accumulate electrons and positrons in a single ring and make them collide, originated in different parts of Europe: Austria, Germany, Norway, UK, France and Italy, in parallel with similar developments in the US and USSR. AdA’s success was due to Bruno Touschek’s extraordinary formation as both an accelerator scientist and a theoretical physicist, and in the unique environment he found in the University of Rome and the Frascati Laboratories, where the post-war reconstruction of Italian physics was taking place, in parallel with the Europe-wide effort, that led to the creation of CERN.