The Memory Cathedral

The Memory Cathedral: A Secret History of Leonardo da Vinci is a historical fantasy novel by the Australian writer Jack Dann, published by Bantam Books in 1995. It has since appeared in ten languages.

The novel works from Leonardo's surviving notebooks and asks what would have happened if the machines in them had actually been built. In Dann's version of the Renaissance, Leonardo constructs a flying machine and travels east, and the military inventions he designed are eventually used in the field while he is in the service of a Syrian general. The book concentrates those events into a single year of his life and treats his curiosity as something that lands on other people as a consequence rather than as a harmless exercise.

The Memory Cathedral was Dann's major historical novel and won the Aurealis Award for best fantasy novel. A novella drawn from it, Da Vinci Rising, won the Nebula Award for best novella in 1996, and the novel was also nominated for the Ditmar Award for best Australian long fiction.