Photograph of the inferior surface of the whole human skull, the Norma Basalis. The irregular surface extends from the incisor teeth at top to the occipital bone at bottom. The large void in lower centre is the foramen magnum, the opening for the spinal cord. At top left and right of the foramen magnum are the occipital condyles, which articulate with processes on the atlas bone of the spine (the first cervical vertebra) in the atlanto-occipital joint: this is where the skull and neck are connected.