Located on the top of the Colle di San Donato , the Medicea Fortress – although often remodeled – is a significant example of the defensive military architecture of the sixteenth century. Under the direction of Antonio da Sangallo the Younger and Nanni Ungheri, the fortification was built between 1538 and 1560 , on the area of ​​the ancient medieval citadel, which was razed to the ground. In the construction a large part of a previous trapezoidal fort was incorporated, which dated back to the beginning of the sixteenth century: two ramparts and some sections of the curtain are still visible in this fort.

The building, initially equipped with three access doors and surrounded by a vast moat, is inserted into the city walls and consists of an irregular pentagonal shape to adapt to the terrain with bastions of considerable height . Very innovative – for those times – was the setting of the western ramparts and that of the internal environments, consisting of a complicated network of rooms, galleries, wells and air intakes, located on various levels.

The Fortress was used until the end of the eighteenth century . In 1800 it was partly dismantled by Napoleon’s soldiers, and the wounds to the structure are still visible. The restoration – already started at the end of the nineteenth century – appears in the programs of the Municipality of Arezzo. From the Fortress you can enjoy one of the best views of the city below and of the Arno Valley.