Abstract: The invention provides a baseboard for use particularly, but not exclusively, as a playboard, as bases for model railway and other track layouts, and for displays, the baseboard comprising a core and a closed box structure surrounding and totally enclosing said core. The core, of an open-cell material, is provided with corner blocks of plastics material, and the edges of the core may be faced with strengthening material.The box structure is formed from a one-piece blank of cardboard material, the blank carrying jointing components so that a plurality of baseboards may be removably connected together.