A load-bearing three-dimensional structure including a skeletal structure formed by a sheet of material having a plurality of bend lines, each bend line including a plurality of folding displacements, wherein the sheet of material is bent along the bend lines into a box-section; and a reinforcing member configured for substantially surrounding a portion of the skeletal structure when bent into a box- section to reinforce the structural integrity of the skeletal structure. A method of manufacturing the three-dimensional structure is also disclosed.