FIELD: construction.SUBSTANCE: invention relates to hydraulic engineering and environment-oriented construction and can be used to protect coastal zones from caving and erosion. Method of erecting the retaining walls includes the manufacture and installation of a coastal fastening comprising two types of retaining walls arranged one above the other. First type consists of two steps 1 and 2, layered together from heavy fascines 3 and gabion mattresses 4. Heavy fascines 3 are made with a diameter of 0.5–0.7 m and a length of 2–2.5 m from bags 5 with a primer sealer and flexible shells made of dense layers of dry reeds 6 and gabion netting, and gabion mattresses 4 are made of lightweight fascines and perforated pipes. Above second stage 2, a second type of retaining walls of reinforced ground structure is constructed, consisting of step-folded gabion mattresses 4 with drainage devices and flexible ground reinforcing arrays 12 of fiberglass materials or geogrid. In this case, gabion mattresses 4 are 2–2.5 m
