Inferior view of the base of the skull. The foramen magnum is the largest foramen on the skull base, through which the spinal cord enters the cranium. The occipital condyles occupy the anterolateral aspects of the foramen magnum and are the site of articulation with the cervical atlas. Prominent foramina visible here for intracranial vasculature include the jugular foramen the carotid canal within the petrous temporal bone. The stylomastoid foramen is the site of cranial access for the facial nerve and stylomastoid artery. The pterygoid fossa is the depression formed between the medial and lateral pterygoid plates of the sphenoid bone, and contains the medial pterygoid and tensor veli palatini muscles. The palatine and maxillary bones comprise the roof of the oral cavity. The vomer is a thin midline bone that articulates posteriorly with the sphenoid and anteriorly with the palatine bone. (Image courtesy of AL Rhoton, Jr.)