stacking a plurality of thin glass plates of a same thickness with a predetermined space between each two adjacent thin glass plates to obtain a multi-layered glass structure in which each two adjacent thin glass plates face each other across the space;

thermally fusing glass on each lateral surface of the multi-layered glass structure to confine the spaces in the multi-layered glass structure;

supporting the multi-layered glass structure containing the confined spaces, using a glass support structure, at an upper surface, a lower surface, and two lateral surfaces opposite to each other with respect to a central axis that is parallel to the upper surface and the lower surface of the multi-layered structure;

heating the multi-layered glass structure together with the glass support structure to collectively soften the multi-layered glass structure and the glass support structure, and drawing the multi-layered glass structure together with the glass support structure in a direction parallel to the central axis; and

cutting the drawn multi-layered glass structure together with the glass support structure in a direction parallel to a second plane that is perpendicular to a first plane that includes the central axis and a stacking direction of the thin glass plates.