Visible blood vessels, also known as spider veins or broken capillaries, appear when the blood that normally flows in and out of the tiny vessels just beneath our skin’s surface pools, causing the vessels to become dilated. This results in small clusters of tiny capillaries—which can appear red, blue, or even green or purple—becoming visible beneath the skin. Broken capillaries are extremely common, and most of us will experience them to some degree throughout our lives, but that doesn’t make them any less bothersome.