The construction of the New Fortress dates back to the end of the 16th century, when the Florentine architect Bernardo Buontalenti was commissioned by the Medici government to draw up an urban plan for the expansion of the new city of Livorno. Work on the construction of the city, based on a pentagonal plan of an “ideal city”, began in 1577, but it was not until around 1589 that it was decided to strengthen the military apparatus by building what would later be called the New Fortress. Work on its construction was fairly rapid, carried out between 1590 and 1594 to designs by Giovanni de’ Medici, Vincenzo Bonanni and Bernardo Buontalenti, while between 1601 and 1603, thousands of slaves and peasants dug the moat surrounding it.
The fortress is an imposing complex in brickwork, bastioned, accessed by a small bridge (at the corner of the Pietre dure and the Arcivescovato canals) and then climbed to the upper part, where there is a public park with a beautiful view of the canals and the city. At the end of the 17th century the complex was largely dismantled to make way for new building spaces in the Venezia district.
The New Fortress was severely affected by World War II bombing, which destroyed most of the buildings inside. The main entrance was originally provided with a drawbridge, later replaced by a stone passage.
The cannon that was fired to announce midday until the early 20th century can still be found inside the fortress.