why the walls of arteries are thicker than the walls of veins?

Arteries are those blood vessels which carries blood away from the heart to the rest of the body, while veins are those blood vessels which bring blood from the various body parts to the heart. Blood flowing away from the heart to the capillaries have more pressure as compared to the blood flowing from the capillaries to the heart. As arteries carry blood from the heart to the capillaries, its walls are thicker and muscular to bear the high pressure of the blood and thus avoiding itself from collapsing. On the other hand, veins have to carry the blood of comparatively less pressure, thus the walls of the arteries are thicker than the walls of the veins.