INSIDE THE SKULL, housed are these areas: anterior fossa, middle fossa, and posterior fossa. The posterior fossa contains the brainstem, cerebellum, and cranial nerves IV-XII. The posterior fossa (orange color) is formed by the occipital bone, which has a large hole (foramen magnum) for passage of the spinal cord. #anatomy
View of the ventral surface of the brain depicting the sites of entry or exit of most of the cranial nerves. Note that the olfactory nerve (cranial nerve [CN] I) is not shown in this illustration and that the trochlear nerve exits the brainstem on the posterior surface and then passes along the exterior of the lower midbrain to enter the cavernous sinus along with CN VI.