Gabions (from Italian gabbione meaning "big cage"; from Italian gabbia and Latin cavea meaning "cage") are cages, cylinders, or boxes filled with soil or sand that are used in civil engineering, road building, and military application. For erosion control caged riprap is used. For dams or foundation construction, cylindrical metal structures are used. In a military context, earth or sand-filled gabions are used to protect artillery crews.I've seen these for years at road construction and shoreline stabilization sites, but never knew what they were called, nor did I realize that the principle had been used in the 16th century to protect cannon emplacements:
In the medieval era, gabions were... made from wickerwork and filled with earth for use as military fortifications. These early military gabions were used to protect field artillery gunners. The wickerwork cylinders were light and could be carried relatively conveniently in the ammunition train, particularly if they were made in several diameters to fit one in another. At the site of use in the field, they could be stood on end, staked in position, and filled with soil to form an effective wall around the gun.You learn something every day.