Apparatus such as a working platform which by means of tension loaded tension member has been anchored and which has been provided with means for mooring a vessel

Apparatus comprising a buoyant body, a plurality of spaced apart vertical tension members which are exclusively designed for taking up tension load, bottom anchors located vertically below the buoyant body and to which lower ends of said vertical tension members are secured, said tension members pulling said buoyant body down against the buoyancy of the buoyant body, said buoyant body having buoyant parts substantially below water level and intersecting the water level with parts which above the water level support a portion for performing operations, the buoyant body carrying said portion for performing operations by means of a single vertical column which extends above the water level and which has horizontal dimensions which are smaller than those of the buoyant body, which column between the buoyant body and the portion for performing operations is surrounded by a rotatable ring having a stationary part connected to the column and a part movable with respect thereto around the column, said movable part having means for mooring a vessel and comprising a rigid arm rotatably connected about a horizontal axis to the movable part of the rotatable ring and at a distance from said horizontal axis being suspended from a vessel by means of a tension member which is loaded by means of a weight of a magnitude sufficient to maintain the vessel substantially in place with respect to the buoyant body, the area around the column and between the portion for performing operations and the top of the buoyant bodies and in which area the rotatable ring with rigid arm is located, being free of obstacles all around the column such that the vessel can freely swing around the column.