Where?
Sardinia!
Before I come to Sardinia, first to the question: Why Europe?
Basically I think that it would send a good signal into the world if Europe realized a peace project in this order of magnitude coming out of the population. Simply because an extremely large amount of violence and genocides have come from Europeans. Also the genocide of the Indians went out in the end from emigrated Europeans. Germany has millions of people of Jewish faith on its conscience, but also, for example, the Belgians executed 10 million Congolese. If you look more intensively into the history of the individual European countries, it becomes unbearable how much violence came specifically from Europeans.
But why Sardinia? Directly for several reasons:
In Sardinia, we find optimal basic conditions to conduct such a large-scale science-based review of the 1980s peace study!