A major multinational study spearheaded by researchers from the National Physical Laboratory and Instituto Nazionale Di Ricerca Metrologica has coordinated optical clocks spanning six countries to establish a new benchmark for redefining the second. Using 38 simultaneous frequency comparisons among ten diverse optical clocks over thousands of kilometers, the research published in Optica highlights progress towards an international optical time scale and enhanced clock precision. These developments promise advancements across domains relying on precise timekeeping, including GPS, financial transactions, and tests of fundamental physics.