In an attempt to understand the details of its construction, a local architect has spent over ten years building a house-sized replica.
How did the craftspeople of six centuries ago construct such an extraordinary structure? Read on through our site to solve the riddle.
Explore the riddle
Find out more
The Victoria and Albert Museum site contains information about Daniel Libeskind and the spiral extension.
Giovanni Fanelli (Scala 1980)
Paolo Galluzzi (Giunti, 1997)