answers: the carotid canal
context: mainly of historical significance. The segments of the internal carotid artery are as follows: The internal carotid artery is a terminal branch of the common carotid artery; it arises around the level of the fourth cervical vertebra when the common carotid bifurcates into this artery and its more superficial counterpart, the external carotid artery. The cervical segment, or C1, or cervical part of the internal carotid, extends from the carotid bifurcation until it enters the carotid canal in the skull anterior to the jugular foramen. At its origin, the internal carotid artery is somewhat dilated. This part of the artery </s> its right side below is the brachiocephalic trunk, and above, the trachea, the inferior thyroid veins, and the remains of the thymus; to its left side are the left vagus and phrenic nerves, left pleura, and lung. The left subclavian artery is posterior and slightly lateral to it. The cervical portions of the common carotids resemble each other so closely that one description will apply to both. Each vessel passes obliquely upward, from behind the sternoclavicular joint to the level of the upper border of the thyroid cartilage, where it divides. At the lower neck the two common carotid arteries </s> from the superior cervical ganglion, and forms this plexus, which follows the internal carotid into the skull. Internal carotid artery The internal carotid artery is a major paired artery, one on each side of the head and neck, in human anatomy. They arise from the common carotid arteries where these bifurcate into the internal and external carotid arteries at cervical vertebral level 3 or 4; the internal carotid artery supplies the brain, while the external carotid nourishes other portions of the head, such as face, scalp, skull, and meninges. Terminologia Anatomica in 1998 subdivided the artery into four parts: "cervical",
question: where does the internal carotid artery enter the skull