Trajan’s Column: Basic Statistics

The Column of Trajan is a monumental single, free-standing commemorative column that stands on a rectangular base, or pedestal.  The Latin term for a free-standing column decorated with a spiral frieze (and/or with an interior spiral staircase) is columna cochlis.  The Column’s order is Doric, or more accurately, Tuscan, as the shaft of the column rests upon a base (a feature lacking in the pure Doric form). At the very top of the shaft, immediately below the capital, 24 Doric flutes are visible.

• Architect: Apollodorus of Damascus (presumed)
• Date of dedication: 12 May of 113 CE (according to Calza’s interpretation of a fragment of the Fasti Ostienses discovered in 1932).
• Shaft construction: 19 drums of Luna (Carrara) marble form the base (sans plinth), shaft, and capital of the Column.  The drums are unequal in height, averaging ca. 1.5 meters each. (Note: Lepper/Frere 1988: 14, report 20 blocks; a number that includes the plinth block – but this is actually of two pieces(?) thus if counted should equal 21 total; they also give average height of shaft columns as 1.44m high). Column drum weight ranges between 29-33 tons; the block for the capital 56 tons.
• Total number of marble blocks used to build the Column: 29, of Luna marble, with an estimated weight of 1,100 tons (Lancaster 1999: 419).

DIMENSIONS

– Total height of Column (including statue base above the capital and pedestal): 38.402 or 129.7 RF (Wilson-Jones/Coarelli).
– Column Height (base-with-plinth+shaft+capital): 29.78m (100.61 R.F.; nb. Wilson-Jones/Coarelli, measured, from the torus: 28.915m). G. Boni (1907a: 3) writes: “The height of the shaft of the column, from the plinth of the base to the abacus on the column, measures exactly one hundred Roman feet.  It was a columna centenaria.” One hundred Roman feet equals 29.60 m.
– Column base (includes plinth) Height = 1.685m (5.692 R.F.); Shaft = 26.92m (90.94 R.F.) Capital = 1.16m (3.92 R.F.)
– Abacus (platform) carried by the capital: 4.34m square (14.66 R.F.); vertical face 65cm.
– Diameter of the shaft at the bottom: 3.695m (12.48 R.F.); at the top: 3.20m (10.81 R.F.).
– Ratio of Column height to base diameter is thus ca. 8:1.
– Pedestal Height 5.29m (17.87 R.F.) Including the Column’s plinth: 6.16m (20.81 R.F.).  Pedestal dimensions: 6.18m square (20.88 R.F.).  More specifics about the pedestal.
(Source of Measurements: Florescu (1969); Lepper/Frere 1988: 13-14; Wilson Jones 2000: 220).  Published measurements are not always equivalent between sources.

• Capital: a Doric echinus decorated with an ovolo molding of 24 eggs.
• Interior spiral staircase: 185 steps.  There are ten windows on each side of the Column (40 total) to illuminate the interior stair.  Each vertical line of windows corresponds to one of the principal “sides” of the Column (defined by the center axis of each face of the pedestal). The height of the helical stairway within the Column is exactly 100 R.F.  (Wilson Jones 2000: 167).
• Figural decoration includes ca. 2,500 figures on a spiral relief that winds 23 times around the shaft for a total length of ca. 200m.  The height of the relief increases towards the top of the Column (0.89m to 1.25m) with a corresponding increase in the heights of individual figures from ca. 60cm to 80cm in height.

ALTERATIONS

The statue of St. Peter and its supporting pedestal were raised into place on September 25, 1588 by the orders of Pope Sixtus V. The statue is the work of Leonardi Sormani and Tommaso della Porta (Brizzi in Coarelli 2000: 239). The fate of the original statue of Trajan which topped the Column is not known – either when it fell or when it was removed or how its bronze was recycled.

Last revised on 22 February 2017.