The Achilles tendon attaches major calf muscles, the gastrocnemius and soleus, to the calcaneous (heel bone). Achilles was a famous Greek warrior whose mother was one of the immortals, but he was not. His mother sought to protect her son by dipping him in the River Styx, which was believed to have magical powers. She held her infant son by his heel. Consequently, the only part of his body that was vulnerable was his heel. As fate would have it, at the battle of Troy, an enemy warrior, Paris, shot an arrow into Achilles heel and killed him. The phrase “Achilles heel” has come into common usage to describe someone’s personal weakness or vulnerability.