Rock, especially gravel, is not often considered a substantial building material on its own, and neither is string; however, when these two elements are combined by laying the string out and entangling it within a pile of rocks to create a solid yet temporary structure. The structure shown above seems to be quite fragile on the surface, but the core is extremely solid due to the tension in the string. Although the uses of this construction type seems quite ambiguous, the potential for temporary strong structures which can be constructed using rubble or scrap materials might be applicable in the future.