Initially called San Pietro for the existence in the square of the church of San Pietro, demolished in the second half of the nineteenth century, but also known as Piazza Grande, to distinguish it from the Small Square located behind the Palazzo del Comune.
The square was much smaller than the current one and closed, on the side facing the sea, by the walls and the Torre del Porto, which overlooked the “Mandracchio”, the ancient port that extended up to half of the current square.
In the evening, a suggestive illumination with blue lights recalls the ancient coast. While on the opposite side the square was bounded by the old Town Hall, the seat of the city administration since the Middle Ages.
During the 1800s, works were made to open the square towards the sea, bury the Mandracchio and create a large garden surrounded by buildings built from the eighteenth to the early twentieth century. After the First World War, with the annexation of Trieste to Italy, the square took the name Unit and from 1955 it became Piazza Unità d’Italia.
12.280 sqm. rectangular plan and on one side opens directly onto the sea. It is the largest square in Europe overlooking the sea.