Which Leonardo da Vinci codex contains many of his engineering and invention sketches?

The Codex Atlanticus contains many of Leonardo da Vinci’s engineering and invention sketches.

This large collection brings together drawings and notes made by Leonardo across several decades. Its pages cover machines, weapons, flight, hydraulics, geometry, and architecture, making it one of the most important sources for studying his inventive work.

The codex is not a single contemporary notebook in its present form. It was assembled from Leonardo’s loose papers after his death and later mounted on large pages. The name refers to the atlas-sized format used for the collection.

The Codex Atlanticus is often confused with the Codex Leicester, which is especially associated with water, astronomy, and natural phenomena. Both contain Leonardo’s writing, but they are distinct collections.