A hard case for housing and transporting objects includes a first shell and a second shell, hinges for connecting the shells and enabling the latter to be arranged in a closed configuration or in an open configuration, and a closing device to lock the shells in the closed configuration. The shells include respective main panels formed by thermoforming an interwoven polypropylene sheet including a plurality of superimposed layers, each layer having oriented polypropylene fibers therein, the layers being arranged to interweave the superimposed fibers, and respective side elements including respective interface edges intended to be coupled to each other in the closed configuration. The side elements are made of polypropylene by injection molding and are fixed to the main panels to carry out respective joining portions in which the injected polypropylene of the side elements and the interwoven polypropylene of the main panels are melted and joined to each other in order to form the shells in a single part and entirely made of polypropylene.