A watertight and thermally insulating tank built into a bearing structure includes at least one wall having a variable width and forming oblique solid angles of intersection with the adjacent walls, the tank includes secondary insulating and watertightness barriers and a primary insulating barrier which are formed by panels fixed to the walls and able to hold a primary watertightness barrier. The vehicle wall or walls and the tent wall or walls, in a design in which they adjoin one another, together form part of a delimiting wall construction, which when erected defines at least one single internal habitable area of the camping vehicle. If the color-shift correction image can not be detected successfully, then the density is increased. Each process block is generally small enough to be mounted on a truck or a flatbed for easy transport, allowing for an assembly line of process blocks to be transported anywhere in the world with ease. The closure remains bound in response to forces upon it. By means of the press fitting, a good sealing action and at the same time low-cost production and mounting are attained.