The meninges (from the word ‘meninx’, which means membrane) refer to the distinct membranous coverings of the brain and spinal cord. The most superficial layer, which is directly underneath the skull, is called the dura mater. The dura mater is tough, fibrous and inextensible. The dura mater is made up of two layers – the periosteal and meningeal. The periosteal layer lines the inner surface of the cranial bones, and the meningeal layer, found deep to the periosteal layer, is continuous with the dura mater of the spinal cord.