Why Are The Walls Of Arteries More Muscular Than The Walls Of Veins?

Arteries are blood vessels that carry blood from the heart to the body. They are elastic and muscular tubes. There are several arteries in the body and they are closely linked to the heart because it carries blood from the heart to the capillaries. On the other hand a vein is the direct opposite of an artery; a vein carries blood from the capillaries to the heart. All veins except the pulmonary vein carry unaerated blood.

The walls of the arteries are found to be thicker than that of a vein because the blood that is carried from the heart to the capillaries has more high pressure. Hence thicker walls are needed to bear that pressure. It is the thickness of these walls that prevent the arteries from collapsing. As the blood flowing through the veins does not have as much pressure as in that of the arteries their walls are thinner as compared to artery walls.

I think that a previous answer may have been wrong. Surely the pressure keeps the arterial walls open whereas the vein walls must be stronger to keep open without the pressure. Is not the situation analogous to that of the outlet and inlet pipes of a water pump?