The tiburio is a structure located on the Milan Cathedral in Milan, Italy. It is most notable for being the first construction project Leonardo da Vinci took part in. While the style of the tower is Gothic, the methods used in its design are Renaissance. The challenge was to create one that would stand over the cathedral's crossing area. da Vinci proposed a design that was in the shape of a square, stating that it would be much stronger than that of an octagon. He drew a system of buttresses that would hold the tower and strengthen the building's infrastructure. His design would be change into a more octagonal layout, but his experience would lead him to continue creating drawings for potential buildings.
Source: Isaacson, Walter. Leonardo Da Vinci. Simon & Schuster, 2017.
