The Mouth of Truth is a big antique marble mask which was built in the wall of the pronaos, or inner area of the portico, of the Church of Saint Mary in Cosmedin.

The Mouth of Truth was a manhole cover in ancient Roman times: in fact, it is decorated with an effigy of a fluvial god who “swallows” rainwater.

The mask represents a male bearded face and its eyes, nose and mouth are holes.

It has acquired legendary fame since the middle ages, because legend says that whoever puts their hand in the mouth and does not tell the truth will have it brutally cut off.

The whole area around the Church of Santa Maria in Cosmedin is magnificent, thanks to its immense eternal marvels such as the Temple to Hercules the Winner, the Temple to Portunus, the Fountain of the Tritons, the Arch of the Argentarians and the Arc of Janus.