<span>The ventricular system consists of four ventricles that are interconnected in the brain. The third ventricle</span> is the portion of the ventricular system is found within the diencephalon. It is a median cleft in the diencephalon between the two thalami, and is filled with cerebrospinal fluid (CSF). The hypothalamus is the gland located within the floor of the this ventricle.
