The Sirente crater is a circular small lake in the valley of Sirente, in the Sirente Velino Regional Park, about 13 km from Secinaro. For several decades, the science has been interested in it for its presumed extraterrestrial origin. It was the eminent Swedish geologist Jens Ormo in 1990 to suppose that a meteorite created the raised-edge lake.
Although science has not yet confirmed the thesis of the Swedish scholar, some historical evidence has already been found. Even the glow that in 312 AD induced the Emperor Constantine to convert himself to Christianity is related to that meteorite. For further information and curios, please refer to the National Geographic website.