The gate and walls of Largo Parlascio were built in 1157. Porta Parlascio takes its name from the toponym referring to the area to the northeast of the city, likely of Lombard origin. The importance of the gate was highlighted by the presence of brackets decorated with vegetal motifs and the size of the arch opening, the largest of all the city gates. In fact, the large dimensions required a reduction shortly after construction, as evidenced by the still-visible brick sub-arch.
Porta Parlascio was a fortified entrance: it had two stone towers on its outer sides, serving as control and defense points. After the first Florentine conquest of the city in the early 15th century, the gate was further strengthened with the addition of a counter-gate designed by Filippo Brunelleschi. In 1543, the medieval structure was transformed into a bastion by architect Nanni Unghero, with the pentagonal bastion still preserved today, permanently blocking access beneath the gate.
The bastion has been fully restored and now houses an additional entrance to the Walls and the multimedia exhibition space Pisa Time Machine.
