A lid arrangement comprising: first and second lids (22, 22A) for use in a container comprising a wall arrangement, each lid being movable between open and closed positions; each lid (22, 22A) comprises opposite free and hinged edges (126, 124), and a plurality of rib formations extending transverse to the aforesaid edges (126, 124); wherein when the first and second lids (22, 22A) are in the closed positions, the rib formations of the first lid overlap the rib formations of the second lid at the respective free edges; and wherein the free edge of each of the first and second lids (22, 22A) overlap each other when the lids (22, 22A) are in the closed positions, and wherein adjacent rib formations of the first lid provide a first projecting portion at the free edge of the first lid, and adjacent rib formations of the second lid provide a second projecting portion at the free edge of the second lid, whereby when the first and second lids (22, 22A) are in their closed positions, the projecting portions (138, 140) of each of the first and second lids (22, 22A) extend across the free edge of the other of the first and second lids (22, 22A); characterised in that the rib formations extend substantially wholly across the first and second lids (22, 22A) obliquely from the hinged edge to the respective first and second projecting portions, wherein when the first and second lids (22, 22A) are in the closed positions, each rib formation of the first lid extends parallel to, and alongside, a corresponding rib formation of the second lid to provide a line of support that extends across the lid arrangement from the hinged edge of the first lid to the hinged edge of the second lid. first and second lids (22, 22A) for use in a container comprising a wall arrangement, each lid being movable between open and closed positions; each lid (22, 22A) comprises opposite free and hinged edges (126, 124), and a plurality of rib formations extending transverse to the aforesaid edges (126, 124); wherein when the first and second lids (22, 22A) are in the closed positions, the rib formations of the first lid overlap the rib formations of the second lid at the respective free edges; and wherein the free edge of each of the first and second lids (22, 22A) overlap each other when the lids (22, 22A) are in the closed positions, and wherein adjacent rib formations of the first lid provide a first projecting portion at the free edge of the first lid, and adjacent rib formations of the second lid provide a second projecting portion at the free edge of the second lid, whereby when the first and second lids (22, 22A) are in their closed positions, the projecting portions (138, 140) of each of the first and second lids (22, 22A) extend across the free edge of the other of the first and second lids (22, 22A); characterised in that the rib formations extend substantially wholly across the first and second lids (22, 22A) obliquely from the hinged edge to the respective first and second projecting portions, wherein when the first and second lids (22, 22A) are in the closed positions, each rib formation of the first lid extends parallel to, and alongside, a corresponding rib formation of the second lid to provide a line of support that extends across the lid arrangement from the hinged edge of the first lid to the hinged edge of the second lid.