I have no idea what the English version of the day is because, despite the eagerness of Italian newspapers (see here and here) to promote the initiative as “international”, no trace of “La Giornata Mondiale Della Lentezza” can be found outside of Italy.
This slow-down initiative, which has been organised by an association in Pavia, has only one scope: to “hold on a moment, slow down a bit, retake our time”.
And it has been surprisingly successful in Italy with a slow marathon in Rome, symbolic fines for the most frenetic Milanese, a slow bicycle race in Ferrara (the slowest wins!), donkey rides in Pisa, and poetry in the supermarkets of Cagliari.
Apparently something also happened in Heidelberg, Germany.