Walls were the first painting supports. These mural paintings still exist today after twenty thousand years of protection deep inside ancient caves in India and France.PAPYRUS: Papyrus is soaked, pressed and dried as strips of pith. it's a member of the sedge family. Papyrus was once abundant in Egypt and used by the Greeks and Romans as paper.
PAPER: Paper is also made of wood, cotton and linen. Linen is best, but cotton will do. Cotton paper is called rag 100%. The paper is glued throughout with an animal size. This is called vat sizing, and it is to be preferred. The papers I've found best are; a new paper hand-made called Twinrocker, Whatman, Strathmore, Lanaquarelle, Fabriano, Winsor & Newton, D'Arches and Waterford. They are all pH-neutral, vat and surface sized.