Abstract: A retaining net is made of wire rings which are interlooped when producing at least some of the rings while other rings that participate in the interlooping are prefabricated. Such nets are used for protection against falling rocks, avalanches, and mud slides. The interlooping rings are formed by feeding a wire (22) through a bending tool (15) to form several turns that interloop with at least two prefabricated rings (20A, 20B) that are held by suspender members (31) so that the rings (20 being formed extend crosswise to the prefabricated rings. When the formation of a first row of interlooped rings is completed, that row is interlooped with a second row and so forth. The interlooped ring structure provides a simple, cost effective construction method for strong retaining nets.