The meninges are three connective tissue coverings that surround, protect, and suspend the brain and spinal cord within the cranial cavity and vertebral canal.
Those tissue are:
- the dura mater is the thickest and most external of the coverings;
- the arachnoid mater is against the internal surface of the dura mater;
- the pia mater is adherent to the brain and spinal cord.
Between the arachnoid and pia mater is the subarachnoid space, which contains CSF.