A package of cigarettes having a group (4) of cigarettes; an inner package (3) which encloses the group (4) of cigarettes, is defined by a sheet (22) of transparent, heat-seal plastic packing material folded directly about the group (4) of cigarettes and in direct contact with the cigarettes, and is stabilized by heat sealing; and a U-shaped stiffener (23) of rigid material located inside the inner package (3) and contacting the group (4) of cigarettes.