Detail of the Bridge over the Danube on the Column of Trajan in Rome, July 2012

Like an unrolled scroll, a spiral frieze winds twenty-three times around the column, depicting the campaigns of Trajan in Dacia in AD 101-102 and AD 105-106. It likely illustrates the emperor's own commentary on the wars, a book, now lost, that was housed in the adjacent library. Depicted in low relief, there are one hundred and fifty-five scenes, in which more than twenty-five hundred figures are represented, no less than sixty of Trajan, himself. Only eighteen scenes actually depict battles; most show the day-to-day activities of the army. Situated between the two libraries and enclosed by a peristyle, only the elaborately decorated base was not obstructed from view, and it is not certain if these scenes could be appreciated or even were ignored once the column had been erected.

At the top was a statue of the emperor in gilt bronze, access to which was by a spiral staircase illuminated by a series of slit windows cut into the marble.

Text from: penelope.uchicago.edu/~grout/encyclopaedia_romana/imperia...