Traditional ger or yurts consist of a circular wooden frame carrying a felt cover. The felt is made from the wool of the flocks of sheep that accompany most nomads. The timber to make the external structure is not found on the treeless steppes so must be bought or traded for in the towns or village. The frame consists of lattice wall sections, a door frame, roof poles and a crown. Some ger have columns to support the crown. The frame is covered with pieces of felt which is then covered with canvas for waterproofing and windproofing.