Once only indicated through a sketch by Leonardo da Vinci from around 1495, concealed passageways have been discovered ...

A long-rumored network of secret tunnels sketched by Leonardo da Vinci has been uncovered beneath the Sforza Castle in Milan, ...

During this period, Leonardo produced sketches of defensive structures that closely resemble the layout of the Sforza Castle, including the Ghirlanda and multiple passage systems around it.

The duke had commissioned the artist for a painting and during this time, da Vinci created the drawings of defensive structures that closely resemble the layout of the Sforza Castle.

During this period, Leonardo produced the drawings of defensive structures that closely resemble the layout of the Sforza Castle, including the Ghirlanda and multiple passage systems.