A plurality of fibers or one-dimensional, two-dimensional, or three-dimensional fibrous structures are provided, having fibers from a first raw fiber material. The first raw fiber material contains unsubstituted or partially substituted polyvinyl alcohol and/or unsubstituted or partially substituted polyvinyl alcohol copolymer. The fibers can be crosslinked by tempering the fibers or fibrous structures, with the result that the fibers or the fibrous structure are configured to be gel, in particular hydrogel, fibers or fibrous structures and have excellent stability.