For his forum Caesar chose a central position at the foot of the Capitol, near the old Roman forum. In order to clear the site he had to relocate the Curia Hostilia and the Comtium and purchase and demolish the elegant houses already in situ. Caesar’s forum was rectangular and extended form the Curia (east) to Via di S. Pietro in Carcere (west), the long sides running more or less parallel with the Clivus Aregentarius. Domitian engaged in restoration work, probably on account of the fire which destroyed part of the Capitol in 80. Trajan completed the work. About two thirds of Caesar’s forum has been uncovered, the rest is beneath the Via dei Fori Imperiali.
The piazza, in a long rectangular form, had columnar porticos on the sides with two naves. Meanwhile, the entrance side had only a one nave portico, probably for the presence of the Chalcidicum- the monumental entrance to the Curia.
Under the flat ceilings of the lateral porticos were a series of tabernae (shops) from the Augustus era that were partially reconstructed under Trajan. The shops, of various sizes, were wedged in the Campidoglio facing Clivo Argentario- the antique street that connected the Roman Forum to the Campidoglio.
A semicircular series of columns facing south-east gave access to a large public lavatory from the Trajan era and is considered to be the largest in the antique world.
As an extension to the south-west portico, Trajan also added a structure of pillars with double naves and two wings running along the edge of the Campidoglio.
According to sources from the 4th century A.D. the Forum was later used as the Basilica Argentaria, which certainly reflected the name of its location-Clivo Argentario. At the end of the Forum piazza was the Temple of Venus Genetrix with eight columns in the front, nine on the sides, but without any columns in the back (periptero sine postico).
Functions
The Forum wasn't used for commercial activity, but used as a meeting place for dealings in public affairs as well as the noblest activities that were before held in the Roman Forum.
The Basilica Argentaria was probably used as a specialized market selling bronze and silverware. In later ages the structure was certainly used as a school. The temple's cell probably also functioned as a museum since several works from celebrated artists have been found: one of them being the worship statue of Venus sculpted by Arkesilaos-celebrated artist in Caesar's time. Together with this are preserved paintings by Timomaco of Bisanzio, six dactylothecae (incised precious stones), and a gold statue of Cleopatra.
Historical Context
The Forum of Caesar, in addition to being one of the most evident monuments of self-representation of political power, was constructed as an extension to the Roman Forum. Caesar himself behaved like a greco-oriental sovereign, escorted by a procession of elephants and, against every republican norm, once received the Senate sitting in the center of the temple. The dictator also had placed in front the temple a statue of himself riding Bucefalo, the celebrated horse of Alexander the Great and symbol of absolute power. The Temple of Venus Genetrix, intentionally placed at the end of the piazza was the unifying and conclusive element to the architectural complex. This strict centralized vision corresponded to the ideological function, following the propaganda of the Hellenistic sanctuaries.
The choice of the Forum site is also significant: the future dictator didn't want to be far from the central power, represented in the Curia, seat of the Senate. In fact, not long before Caesar's death, the Senate agreed to reconstruct the Curia on the site.
The Public Lavatories

 The semicircular brick structure had a loose stone foundation under the pavement with suspensurae (small brick pillars) inserted for drainage.
The external area was probably covered with a ring barrel vault, while the central sector was presumably uncovered to give light and ventilation. In spite of its modest function as public toilets, the walls were covered in marble- evident today by holes in the walls that were used to place the slabs.
Travertine corbels supported seats for around 50 people. This is an example of one of the largest and most elegant hygienic foundations in the antique world.
Graffiti on walls
In the late antique epoch the Basilicata Argentaria was used as a school, as attested by graffiti of verses from the Aeneid. These are still visible on the plaster of the walls.
It is guessed that one of the teachers was Caecilius Eros. There is not only graffiti in writing but also a series of comical figures and portraits probably done by bored students.
Decorative Elements
The rich architectural decoration of the Temple of Venus Genetrix, re-erected by Trajan, was reconstructed based on both historical sources (over the ages this decoration has recorded magnificence) and recovered fragments found during the 1930's excavation- recently renovated and systemized in the inside of the tabernae.