Abstract: Structures for providing a stable platform in or above the water and capable of surviving extreme environmental conditions and of minimizing risk and damage to itself and to vessels in the event of a collision. A disclosed structure includes a base mooring element fixed to the seafloor, a positively buoyant column having a base end and an opposite end, at least one articulated joint between the column base end and the base mooring element permitting pivotal movement of the column, and at least one elastic element connected to the column for urging the column towards an equilibrium position and for providing a restoring force following displacements of the column from the equilibrium position. Significantly, buoyancy primarily serves the function of returning the column to a vertical or near-vertical position to facilitate location and repair in the event an elastic element is broken.