The internal jugular veins are large blood vessels located in the neck. They are responsible for draining deoxygenated blood from the brain, face, and neck back to the heart. These veins run alongside the carotid arteries, which supply oxygenated blood to the brain. Each internal jugular vein begins at the base of the skull and descends down the neck, eventually merging with the subclavian veins to form the brachiocephalic veins. They play a crucial role in the body's circulatory system, ensuring that blood is efficiently returned to the heart for reoxygenation.