The part of the aorta which is contained within the thorax is named the ascending aorta, the arch of the aorta, and the descending aorta.

The visceral branches of the descending thoracic aorta supply the lungs, pericardium, oesophagus and posterior mediastinal.

The parietal branches are the intercostal. They run outward over the bodies of the vertebrae, under the gangliated cord of the sympathetic, one in each of the nine lower intercostal spaces. Each artery is accompanied by a nerve and a vein.

They run along the borders of the ribs, a posterior branch divides into a spinal branch to the cord and a muscular branch.