SkullThe bone of the skull. The dura mater lines its inner surface.
Endosteal layer of the duraThe outer layer of the dura mater. It is stuck to the inside of the skull like a lining. Also called the periosteal layer.
Meningeal layer of the duraThe inner layer of the dura mater. Where it parts from the outer layer it encloses the venous sinuses, and it folds down between the hemispheres as the falx cerebri.
Superior sagittal sinusA channel for venous blood between the two layers of the dura. It runs along the top of the midline.
Falx cerebriA sickle-shaped fold of the dura's inner layer. It dips down between the two hemispheres of the brain.
Arachnoid materThe thin middle membrane, under the dura. Fine threads cross from it to the pia mater.
Subarachnoid spaceLies between arachnoid and pia mater, filled with cerebrospinal fluid.
Pia materThe thinnest, innermost membrane. It hugs the surface of the brain and follows it down into every fold.
Cerebral cortexThe brain's folded outer layer of grey matter, under the meninges.
How this list was compiled: Read 2026-09-27. (1) Gray's Anatomy of the Human Body, 20th edition (1918), The Meninges of the Brain and Medulla Spinalis, https://www.bartleby.com/107/193.html : three membranes, from without inward the dura mater, the arachnoid and the pia mater; the cranial dura lining the skull as an internal periosteum, in two layers, an outer endosteal and an inner meningeal, which separate to form the venous sinuses; the falx cerebri, a fold of the inner layer, containing the superior sagittal sinus; the subdural space; the subarachnoid cavity filled with cerebrospinal fluid; connective-tissue trabeculae; arachnoid granulations beside the superior sagittal sinus; the pia mater on the cortex. (2) Wikipedia, Meninges, https://en.wikipedia.org/wiki/Meninges : the dura mater, arachnoid mater and pia mater; the dura's outer endosteal (periosteal) layer by the skull and inner meningeal layer, separating to surround the dural venous sinuses; the falx cerebri, the largest dural fold; the subarachnoid space between arachnoid and pia, containing cerebrospinal fluid, crossed by arachnoid trabeculae; the arachnoid granulations. Licence: own work
The drawing: Drawn for this site by script, 2026-09-27. Own work, nothing traced. Licence: own work
How it works
These are the layers of the meninges, the three membranes round the brain, in a slice across the top of the head from the skull down to the cerebral cortex, with the midline in the middle.
Read the full guide
From the skull in
The dura mater lines the skull in two layers: the endosteal layer against the bone and the meningeal layer inside it. At the midline they part round the superior sagittal sinus, and the inner layer dips between the hemispheres as the falx cerebri.
Down to the brain
Under the dura is the thin arachnoid mater. Below it the subarachnoid space holds cerebrospinal fluid, crossed by fine threads. The pia mater hugs the cerebral cortex, following every fold. The spinal cord is wrapped in the same three membranes.
Remember the order with PAD, from the brain out: pia, arachnoid, dura.
Questions and answers
What are the three layers of the meninges?
From the outside in: dura mater, arachnoid mater, pia mater. The dura is tough and thick; the pia is delicate and lies on the brain itself.
Where is the cerebrospinal fluid?
In the subarachnoid space, between the arachnoid mater and the pia mater, all round the brain and the spinal cord.
What is the falx cerebri?
A sickle-shaped fold of the dura's inner layer that dips down between the brain's two hemispheres. The superior sagittal sinus runs along its top edge.