Varicose veins are swollen, dark blue or purple blood vessels that you can usually see and feel beneath the skin. They often look like twisted ropes, and usually appear on the thighs, calves, and ankles. Some patients with varicose veins are free from symptoms. Most however develop aching, throbbing, cramping and or pain that may indicate the need for medical attention. Sometimes, however, more significant problems including bleeding, ulcers, blood clots, pulmonary embolus, and or death can develop if abnormal veins are left untreated.