Course
It arises from the confluence of the two vertebral arteries at the junction between the medulla oblongata and the pons.
It ascends in the central gutter (sulcus basilaris) inferior to the pons and divides into the posterior cerebral arteries and the superior cerebellar artery just inferior to the pituitary stalk.
From the basilar artery arises the anterior inferior cerebellar artery (supplying the superior and inferior aspects of the cerebellum), as well as smaller branches for the supply of the pons (the pontine branches).
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