We are so used to seeing it, grim and massive in its stone cladding, that we do not ask ourselves why the tower is so decentralized, nor the strange and composite shape of the rear part, so different from the front block facing the square. The only one, this, at the time when the Palace was built as the seat of the Priors of the city. The three courtyards clearly testify to the subsequent additions, due to the new needs of the Grand Ducal family first, of the Kingdom then, when Florence became the capital.

Few people know the historical events of the Palace: its rise on the ruins of the houses of the Uberti, execrated leaders of the Ghibelline faction, the progressive incorporation of ancient wall structures, the continuous changes made to the stairs, rooms, decorations ...

Here is the small door visible at the top of the first courtyard, which seems absurd to those who do not know or do not remember that it was reached by a wooden staircase, to be dismantled in the event of an enemy attack because it led to the Hall of Weapons. Or the visible stone cladding, on the left, at the top of the staircase facing its twin that leads to the Sala dei Cinquecento. Why here, inside, the boulder that covers the outside of the original nucleus of the Palace? Simple: it is the wall that belonged to the back of the first massive structure and which, from outside, has become internal after the new additions.

In the same way, the external loggia of access to the Salone dei Duecento has disappeared; the ceiling of that of the sixteenth century has been raised, which therefore has a very different appearance from when it hosted the trial of Savonarola. Nor does the Arengario exist anymore - the rise that ran along the main facade - from which the Priors attended the celebrations and spoke to the people; the ancient lion has crumbled, the original by Donatello is in the Bargello, as are many other copies of the statues that dot the Loggia dei Lanzi and the square.

These and others structural and decorative changes, implemented over the centuries at the behest of the Medici, they are visible to all. What, however, is not seen and that most people ignore, is that the thick walls of the Palace are crossed by an infinite series of tunnels and hidden passages, with small windows (like the one that opens into the loggia which is accessed from Eleonora's rooms) and peepholes from which it was possible to invisibly watch political meetings and confidential talks; that you can go from one room to another by opening secret doors like the one hidden behind one of the maps of the Sala del Mappamondo; or look into the square from one of the rare windows hidden behind the coats of arms that adorn the facade.

And then labyrinths of streets and burella from the Roman age hidden under the ground floor pavement; narrow corridors through the thickness of the walls; hatches in ceilings and floors; stairs destroyed, walled up, disappeared, wells that end directly in the Scheraggio and then in the Arno.

Stories of mysterious and dark are told attendance who wander in the splendid halls: restless spirits of courtiers, spies, servants, killed by the sword or thrown into the second courtyard or thrown into the Scheraggio - the underground river to build the Palace and who, descending from the Studiolo del Principe in the premises below, you can hear tumultuous flow.

Black legends that are added to the others circulating about the Medici and which suddenly returned to the fore when the excavations carried out in via dei Leoni to house the Immigration Office brought to light three ancient skeletons. Legends of struggles for power, of opposed loves, of unpunished assassinations. Like that of Cosimo's servant who suddenly disappeared, perhaps walled up alive because he was guilty of having revealed to the future Francesco I the relationship of the elderly Grand Duke with the young and unpopular Camilla Martelli.

No one has ever seen them, the ghosts of Palazzo Vecchio, but there are those who whisper that they have sensed their presence ...