Originally the Roman city gate, built in the first century AD on foundations from the 1st century BC, was reconstructed in the year 265. The original gate included a fortified and rectangular structure that included an inner courtyard, watchtowers and paths for the sentries that guarded it.
Above the gate that remains today, you will see a two-story wall with 12 arched windows, some inside small niches. On the side, note the columns of the Corinthian columns that support Architrave, the first occurrence above the column capitals and the Pediment, the triangular element at the front.
In the days of the Roman Empire, Porta dei Borsari was one of the most important gates of the city and served as an example of many defensive gates built over the years throughout the empire. The Roman name of the gate was Porta Iovia, because of the temple of Jupiter, Iovianus, which was nearby.
In the Middle Ages it was called the gate of San Zeno. The gate has inspired many important architects over the years.