The plantar fascia is a ligament attached to the heel bone (calcaneus). It divides and fans out to attach to the bones at the base of the toes. These bones are called the metatarsal bones. Layers of muscles, tendons, nerves, and blood vessels run over the bottom of the foot. The plantar fascia covers these layers and acts as a bowstring on the bottom of the foot, helping the bones of the foot maintain the arch. A fat pad covers the plantar fascia beneath the heel bone. This pad cushions the heel as it takes the force of each footstep.