The vertebral artery (VA) is the first cephalad branch of the subclavian artery. From a trauma surgery perspective, the VA is divided into three parts. Part I runs from its origin at the subclavian artery to C6, where it enters the transverse foramen. Part II courses in the bony vertebral canal, formed by the transverse foramen of C6 to C1. Part III runs outside the vertebral canal, from C1 to the base of the skull. The VA enters the skull through the foramen magnum, piercing the dura mater. It joins the contralateral VA to form the basilar artery, which is part of the circle of Willis.

The first part of the VA can be landmarked externally by the triangle formed by the sternal and clavicular heads of the sternocleidomastoid (SCM) muscle and the clavicle. It runs upward and backward between the anterior scalene and longus colli muscles, before entering the vertebral canal at the C6 level.

The carotid sheath is anterior and medial to the first part of the VA.

The external landmark of C6, where the VA enters into the vertebral canal and the second part of the VA begins, is the cricoid cartilage.

The VA is surrounded by a venous plexus.