The fibrous tissue that surrounds muscle and separates many tissues of your body is called the fascia. The underside, or plantar, area in the foot features a strip of the rough tissue, called the plantar fascia, stretching within the heel towards the entrance of The underside from the foot. Verywell https://www.theorthopaedicandpainpractice.com/treating-foot-arch-pain-with-modern-orthopaedic-pain-management-techniques/