Spider veins, or telangiectasias, are enlarged blood vessels below the skin's surface. They often appear on the thighs, calves, feet, or under the knees. They can be blue, purple, or red.

Spider veins, the more delicate red or blue tracings that can pop up on the skin's surface like kinky spider webs, are a minor form of varicose veins and can precede development of the more ...