The cerebrovascular system is a term for the blood vessels that carry blood to and from the brain. The heart pumps oxygen- and nutrient-laden blood to the brain, face, and scalp via two major sets of vessels: the carotid arteries and the vertebral arteries. The carotid arteries run along the front of the neck – one on the left and one on the right. The vertebral arteries travel along the spinal column. At the base of the brain, the carotid and vertebrobasilar arteries form a circle of communicating arteries known as the Circle of Willis. A blockage of blood flow in the arteries can cause a stroke.