The external iliac is a continuation of the femoral vein. It extends upward along the pelvis eventually joining with the internal iliac to form the common iliac vein. The left common iliac and right common iliac veins converge to form the inferior vena cava. The iliac veins receive blood from the lower extremities and pelvis. The external iliac contains one or two valves, while the internal iliac and common iliac veins do not have any.