Olfactory nerve tracts

The structure that is commonly called the olfactory n. (CN I) is actually a nerve tract that grows out from the brain during development. The olfactory nerve tracts connect the olfactory bulb to the olfactory processing regions of the brain.  The nerve tracts are made up of the axons of mitral cells (“projection neuron” in the image below), which synapse with olfactory neurons in the olfactory bulb.