The fort was built between 1590 and 1595 for Grand Duke Ferdinando l de Medici and was designed by Bernado Buontalenti. It was built to protect the city and the Medici rule. It was also used to hold the Medici treasury. The fort was connected to the Palazza Vecchio via the Vasari Corridor and paths in the Boboli Gardens.
Inside the fort a villa was built as a place for the Grand Duke to use during times of unrest, it was a luxurious palace and was unlike the rest of the fort. This area was also a place where witches used to be burned at the stake. Today it is open to the public and is used for many different things such as exhibitions.
There have been many strange things happen in and around the fort such as the sound of children laughing, singing, people talking and also several ghosts have been sighted.