Private security at Rome's Colosseum caught a tourist carving his name onto a pillar on the ancient structure, CNN reported.
The tourist, identified as a 32-year-old man visiting from Ireland, used a metal point to inscribe his first and last initials on the structure's first floor.
In Italy, damaging a historical or artistic landmark is a crime that could result in up to one year in prison or a minimum fine of $2,400 (€2,065).
One tourist who was caught carving a letter into the walls of the Colosseum in 2014 was fined more than $23,000 (€20,000) and charged with four months in prison.
