Arteries also contain a strong, muscular middle layer that helps pump blood through the body. ... Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don't require valves because pressure from the heart is so strong that blood is only able to flow in one direction.)

Which arteries have no valves?

Usually arteries do not have valves. But two arteries originating from right and left ventricles have valves to prevent backflow of blood. These two valves ( aortic and pulmonary) are usually regarded as heart valves.

Where are valves not found?

Valves are present only in the veins and not in the capillaries and arteries.