A single box gabion is disclosed. The gabion comprises interconnected side walls. Each side wall comprises at least one substantially closed side wall element panel that prevents a gabion fill material from falling through the side wall without the aid of a gabion lining material. The single box gabion can be coupled together to form a modular gabion structure to protect military or civilian installations from weapons assault or from elemental forces, such as flood waters, lava flows, avalanches, soil instability, slope erosion and the like.