A border wall or fence is constructed from a plurality of existing ISO steel shipping containers which are connected together both horizontally and vertically at their corners using conventional corner locks so as to present a continuous physical barrier of any selected length. The containers are stacked three or four high with the bottommost containers recessed into the ground and filled at least partially with dirt or sand. The uppermost containers are open at their ends to allow personnel to walk or drive through the length of the wall. Windows are also formed in the upper containers to allow personnel to view the area around the wall. Gated openings can be formed periodically to allow for passage through the wall.