Art, history, and modern technology helped researchers unveil hidden tunnels beneath Milan’s Castello Sforzesco (Sforza Castle), structures that perfectly match sketches made by Leonardo da Vinci over five centuries ago. 

Built in the 15th century, the Sforza Castle had been originally commissioned by Galeazzo II Visconti in the late 14th century; it was later expanded and fortified by the Sforza dynasty, becoming a symbol of ducal power, of the Sforza family, and of Milan itself. The castle’s sturdy walls and strategic design pay tribute to the military architecture of the time, which dutifully created dwellings at once luxurious and incredibly well-defended.