Information display medium (1) having at least two display faces, one on each of two blank parts (2, 3) made of a substantially rigid and foldable material, the blank parts (2, 3) being arranged so that, when the medium is unfolded, they are stressed so as to stress the display faces, a plurality of holding inserts, which act at various different points along said display faces, being provided to keep the display faces stressed. The blank parts (2, 3) of the display faces are joined together by their edges (14, 19), each holding insert (21) is mounted between the blank parts (2, 3) in a variable position that can switch between a position in which the medium is collapsed and a position in which the display faces of the blank parts (2, 3) of the medium are kept in the stressed state, each insert (21) being associated with a mechanism for locking it in its holding position.