Detailed knowledge of aortic anatomy is necessary before new prostheses can be developed. Our aim was to provide a thorough analysis of aortic arch anatomy in patients who are potential candidates for arch repair. Patients' charts were screened between 2001 and 2019 for all those with a dissection or aneurysm involving aortic arch. Aortic diameters, segmental lengths, aortic arch type, tortuosity, diameters and length of supraaortic vessels were analyzed via computed tomography angiography. We included 558 patients who underwent thoracic aortic treatment for type A, B, non-A non-B dissection, or aortic arch aneurysm. Incidence of all three arch types was similar in patients with type A dissection. In type B dissection and arch aneurysm patients, arch type III was most commonly observed (47% and 52%, respectively). The left vertebral artery offspring from aortic arch was observed in 6.6%. The mid-ascending aorta and aortic arch were not dilated in type B and non-A non-B dissection patients. The innominate, left common carotid and left subclavian arteries median diameters were 16 (14; 18), 8 (7; 9) and 11 (10; 12) mm, respectively. The median innominate artery length was 37 (30; 44) mm. The median left subclavian artery length was 40 (34; 46) mm. Arch types are distributed differently among patients with various arch pathologies. Patients with aortic dissection type B and non-A non-B have a non-dilated ascending aorta and aortic arch. Aortic arch tortuosity, innominate and left subclavian artery lengths do not differ among aortic pathologies.