Trajan’s Column, monument that was erected 106–113 CE by the Roman emperor Trajan. The marble column is of the Roman Doric order, and it measures 125 feet (38 metres) high together with the pedestal, or base, which contains a chamber that served as Trajan’s tomb. Originally the column stood in the middle of a courtyard surrounded by galleries from which one could view at various levels the spiral band (over 800 feet [240 metres] long and about 4 feet [1.2 metres] wide) covered with low-relief sculpture that forms a continuous narrative of the emperor’s two campaigns in Dacia. A spiral staircase is contained within the shaft’s interior, which measures 12 feet 2 inches (3.7 metres) in diameter. At first a bronze eagle had been placed on top of the column and then after Trajan’s death a bronze statue of the deceased emperor, which was replaced in 1588 by a statue of St. Peter.