The invention relates to a method of manufacturing a boat from a single planar sheet of material and comprises the steps of cutting a plurality of notches (120, Fig 2) from the periphery of a sheet of material (10, Fig 1) to form a blank 100, each notch having two opposing edges (110a and 110b, Fig 2)； folding the blank into a three-dimensional shape such that the two opposing edges of each notch meet to form a seam 125, thereby forming an open shell defining the hull of the boat. The application also discloses a method of manufacturing a structure, but in which ribs (300, Fig 4) are fixed over each seam.
