POZZUOLI, Italy — In Greek and Roman mythology, the Campi Flegrei volcano is depicted as the opening to the underworld.
Its prehistoric eruptions blocked out the sun, turning summer into winter and…

POZZUOLI, Italy — In Greek and Roman mythology, the Campi Flegrei volcano is depicted as the opening to the underworld.
Its prehistoric eruptions blocked out the sun, turning summer into winter and…