Sant'Ambrogio, Roman marble column in Piazza Sant'Ambrogio, Italy

The Colonna del Diavolo, also called the imperial column, is a single column of cipollino marble topped by a Corinthian capital, set in Piazza Sant'Ambrogio before the basilica. Two holes pierce the stone, the marks that local legend attributes to the devil's horns.

The column belonged to the Roman imperial palace built by Emperor Maximian at the end of the 3rd century, when Mediolanum became capital of the Western Roman Empire (286–402). It was found in the 19th century during excavations in the area of the ad martyres cemetery, lying on a tomb. Galvano Fiamma records that Holy Roman Emperors embraced it at their coronation as King of Italy, and a 1507 document assigns the same duty to prefects.

The column is connected to a local legend about Saint Ambrose confronting evil forces at this spot, leaving marks that visitors can still observe. This story remains part of how locals understand and relate to the place.

The column sits on a central plaza and is easily reached on foot, especially when using public transit. The square is open and accessible at any time, with fewer crowds typically in the early morning hours.

Many visitors overlook that the two holes at the base were traditionally believed to serve as a connection to supernatural forces. This idea has captivated generations of locals and shaped how people experience the monument.