The remains of the Temple of Apollo (or Zeus for others). This majestic ruins dates back to the second century AD on lake Avernus which is a volcanic crater lake born some 4,000 years ago. The Temple is located in the Campania region of southern Italy, northwest of Pozzuoli.
If you stand perfectly still in front of the temple you can hear swords clashing and sandals crunching on gravel from a Steve Reeves Hercules movie.