When the Second International decided at its founding congress in 1889 to organize a large international demonstration on May 1st in all countries, it remained open how this should take place. This question has led to ongoing debates to this day, so that May 1st has oscillated between the poles of a day of struggle and a festive day, as well as between the revolutionary and reformist goals of the labor movement since its inception. This work connects to the paradigm significance of May 1st by understanding the history and present of this day as a seismograph for the culture, value orientation, and future perspectives of the labor movement. For the first time, a comprehensive analysis of the May celebrations in Switzerland from their beginnings to the present is presented. It draws comparisons between May 1st in urban and rural areas.