Visible from Via dei Fori Imperiali and Via Alessandrina, the forums of Trajan, Augustus, Nerva and Caesar are known collectively as the Imperial Forums. These were largely buried when Mussolini bulldozed Via dei Fori Imperiali through the area in 1933, but excavations have since unearthed much of them. The standout sights are the Mercati di Traiano (Trajan's Markets), accessible through the Museo dei Fori Imperiali, and the landmark Colonna Traiana.
Visits, by guided tour only, must be booked in advance.
Little recognisable remains of the Foro di Traiano, except for some pillars from the Basilica Ulpia and the Colonna Traiana, whose minutely detailed reliefs celebrate Trajan's military victories over the Dacians (from modern-day Romania).
To the southeast, three temple columns arise from the ruins of the Foro di Augusto, now mostly under Via dei Fori Imperiali. The 30m-high wall behind the forum was built to protect it from the fires that frequently swept down from the nearby Suburra slums.
The Foro di Nerva was also buried by Mussolini's road-building, although part of a temple dedicated to Minerva still stands. Originally, it would have connected the Foro di Augusto to the 1st-century Foro di Vespasiano, also known as the Foro della Pace (Forum of Peace). On the other side of the road, three columns on a raised platform are the most visible remains of the Foro di Cesare.