In Naples, the media-fanned controversy over the drilling project momentarily sharpened the ambient danger of living between two volcanoes. When the project went away, the tough questions of inhabiting this beautiful, ferocious place remained. But Neapolitans, as people do, got on with the business of living: on nights when SSC Napoli plays, cafes overflow with demonstrative fans. Clustered around scooters and smoking cigarettes, young people fill the student hangout of Piazza Bellini. Tourists stroll the Lungomare seaside promenade, unknowingly tracing the rough contours of a supervolcano.

On one of my last days in Naples, I catch a bus to the top of Vesuvius, where I find the crater, maw of historic devastation, innocuously smoking. There would be a spectacular view from up here, but the peak is entirely enshrouded, allowing only glimpses of the city through gaps in the clouds; it looks lovely and small. I'm about to head back to the bus when thunder, until now distant-sounding, peals out. It starts to hail, the ice pellets falling fast and hard. Lightning flashes in the clouds. As I trot down the trail, my heart is racing. I know that the probability of me being hit by lightning is very low. But how much, I wonder, have I increased that probability by being at the highest point in the area during a storm? Should I have checked the weather on my smartphone before coming up here? Or avoided the situation entirely? The variables in this calculus of risk multiply, unsolved and unsolvable, and for a moment I truly understand what it means to live atop a supervolcano, or awaiting a superquake. But all I can do now is pull the hood of my raincoat over my head and try to get out of nature's way.

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