will be appreciated that the elements 100a b have minimum overall dimensions when being transported since they can be piled up practically without leaving empty spaces between them and moreover they can be assembled in a three dimensional form which is highly resistant to stress a further advantage consists in the fact that the elements 10a rest on the ground with their walls positioned vertically and are stable without any need for propping a further embodiment of the embankment is shown with 200 and illustrated in fig9 12 the structure 200 essentially includes plate elements 210a 210b comprising a substantially flat wall with connection edges preferably formed with holes or grooves 213 in the shape of a cylinder portion and projecting wall clamps or brackets 215 the elements 210a and 210b in the example illustrated differ from each other only in dimensions the structure 200 preferably comprises also three dimensional elements 210c preferably rectangular or square in plan view provided with connection means along their edges preferably the plate elements 210a and 210b have lengthways dimensions as the sides of the three dimensional element and this preferably has a height double that of the plate element the walls of the three dimensional element can be provided with inspection openings 212 and the.