Back dimples, also known as the dimples of Venus, are sagittally symmetrical indentations visible on the human lower back, just superior to the gluteal cleft. They are directly superficial to the two sacroiliac joints, where the sacrum attaches to the ilium of the pelvis. An imaginary line joining both dimples of Venus passes over the spinous process of the second sacral vertebra. Back dimples are created by a short ligament stretching between the posterior superior iliac spine and the skin. They are congenital, which means that people are born with them. Back dimples are harmless and purely cosmetic. They are more common and prominent in women, but they can also be seen in men. Losing weight can cause back dimples to become more prominent, but there is no muscle in the area to tone, so exercise cannot make them appear. Back dimples are sometimes believed to be a mark of beauty and have been praised for their beauty throughout history.