The collateral fissure is on the tentorial surface of the hemisphere and extends from near the occipital pole to within a short distance of the temporal pole.

Behind, it lies below and lateral to the calcarine fissure

Calcarine fissure

The calcarine fissure is an anatomical landmark located at the caudal end of the medial surface of the brain. Its name comes from the Latin "calcar" meaning "spur."-Anatomy:...

, from which it is separated by the lingual gyrus

Lingual gyrus

The lingual gyrus of the occipital lobe lies between the calcarine sulcus and the posterior part of the collateral sulcus; behind, it reaches the occipital pole; in front, it is continued on to the tentorial surface of the temporal lobe, and joins the parahippocampal gyrus...

; in front, it is situated between the hippocampal gyrus and the anterior part of the fusiform gyrus

Fusiform gyrus

The fusiform gyrus is part of the temporal lobe in Brodmann Area 37. It is also known as the occipitotemporal gyrus. Other sources have the fusiform gyrus above the occipitotemporal gyrus and underneath the parahippocampal gyrus....

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