Trajan's Market Historical Timeline

A complex that was built once and then continuously inhabited for nineteen centuries, which is exactly why so much of it is still standing.

Chronology

1. Probably 100–110 A.D. — the complex is built by Apollodorus of Damascus, the architect who followed Trajan on campaign and whom Trajan entrusted with planning his Forum. Structural impact: the Quirinal slope is cut back and terraced, and the hemicycle is built to follow the Forum's curve. What you see today: essentially the whole surviving structure, including the great curved facade.
2. 1300 — the Torre delle Milizie, the "militia tower", is built as part of the complex's medieval fortification. Structural impact: the Roman fabric is defended and therefore maintained rather than quarried. What you see today: the tower on the skyline above the markets, and the reason the site was never reduced to foundations.
3. Middle Ages — floor levels are added throughout the complex. Structural impact: the Roman rooms are subdivided and re-floored for continued use. What you see today: those added floors, still in place, which is why the interior reads as more storeys than the Romans built.
4. 16th century — a convent is built on the area. Structural impact: another occupying layer on top of the Roman one. What you see today: nothing of it, for the reason two entries down.
5. 1885 — the convent is acquired by the state and becomes the Goffredo Mameli barracks. Structural impact: the site passes into public hands, which is what makes the next step possible. What you see today: the moment the complex stopped being private property.
6. Early 20th century — the barracks is demolished to restore Trajan's Markets. Structural impact: the post-antique accretions are stripped back to expose the Roman complex. What you see today: the site as an archaeological monument, which is a twentieth-century decision as much as a Roman one.
7. 2007 — the Museum of the Imperial Fora opens inside it, holding material from all of ancient Rome's forums. Structural impact: the complex becomes a museum as well as a monument. What you see today: the sculpture and architectural fragments displayed in the Roman rooms themselves.

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