Once upon a time, there was a watchtower that used smoke signals to warn the inhabitants of the approaching Saracen ships to the coast. There are no trace of the ancient structure, but the name of the place continues to bear witness to its existence: Torrefumo (Smoketower).
Of forty thousand years old, after Monte Nuovo, it is the youngest of the thirty volcanoes in the Phlegraean Fields caldera. Although partly located in the Naples area, from an administrative point of view, the Astroni crater falls entirely within the territory of Pozzuoli, while from a geological point of view it falls within the volcanic complex of Agnano.est.