The Arsenal was built in the mid-seventeenth century by the architect Antonio Solari as a weapons depot for distribution to the public in the event of another threat of invasion. Now it contains more than 30 thousand units of the weapon.

The first floor is devoted to heavy rifles, flint pistols and rifles. Here you can also see the field and naval cannons. On the second floor exhibited the armament of cavalry and infantry, and lots of pistols. On the third floor you can see the weapons of the aristocracy, tournament weapons and battle armor. On the fourth floor presents musical instruments of military bands.