On the slopes of Mount Ermada you can visit a karstic cave, the Grotta del Mitreo, frequented since Neolithic times and adapted in Roman times (from the second to the fifth century AD) as a place of worship of the god Mithras. Mithraism is a salvific religion (i.e. based on the existence of an individual’s life after death) of Iranian origin and is linked to the figure of a young man sacrificing a bull in honour of the Sun god: this scene is represented in two limestone reliefs found inside the cave, together with a large number of coins and oil lamps left by the faithful as votive offerings. Some bidders were named in inscriptions identified here, of which, as for the reliefs, the casts are displayed. The location of the place of worship near the resurgences of the Timavo river, where in Roman times the deified watercourse, Diomedes and Saturn, were worshipped, in relation to which the presence of a temple at the present church of S. Giovanni in Tuba is also hypothesized.
