TEHRAN, July 30, YJC - Hot air balloon s from across the globe have lit up the sky in Italy in one of the world's biggest balloon ing events. Organizers described the occasion as the "most relaxed" event on the international balloon ing calendar. Around 60 hot air balloon s lined up at an airstrip near Terni and fired up into the sky. The event stretches over ten days and features occasions for the balloon ists to socialize, often over local food.