Abstract: A barrier structure includes a continuous piece of elongated metal tape. The metal tape includes barbs spaced along an elongate body. Each of the barbs is connected securely to a barb root, and each barb root is connected securely to the elongate body. A first region of the elongate body is adjacent to each barb root, and a second region of the elongate body is adjacent to each first region distal from the barb root. A third region of the elongate body adjacent to each second region distal from the first region extends lengthwise from each second region and meets a corresponding third region that is extending lengthwise away from another second region. Each second region extends transversely and inwardly from the adjacent first region and the adjacent third region.