"The reason of his building a new forum was the vast increase in the
population, and the number of cases to be tried in the courts; for
which the two already existing not affording sufficient space, it was
thought necessary to have a third. He placed statues of the great
Roman generals in both the porticoes of his forum. In building his
forum, he restricted himself in the site, not presuming to compel the
owners of the neighbouring houses to give up their property"
(Suetonius, "Augustus," lvi.).
It was restored by the Emperor Hadrian (Spartianus).