The Mouth of Truth is a large marble face set in the portico of Santa Maria in Cosmedin. Its familiar role as a truth detector belongs to medieval legend; the more likely Roman-era utility of the disk connects it to the city’s ancient water infrastructure.
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The face’s open mouth looks ready to speak, but the stone’s first job was probably much less theatrical. Rome’s tourism office says this large marble disk may have served as a Roman sewer cover, possibly linked to the Cloaca Maxima drainage system.
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UpgradeQuick facts
- The disk is about 1.8 meters across.
- It was placed in the church portico in 1632.
- The name and liar’s-hand legend are documented from the medieval period.
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