The invention relates to a mooring system, comprising a tanker (1,9,15,22,72,86,104,131) and a device (5,11,20,61,74,95,111,135) having some type of anchor (3,10,23,66,71,68,77,113,140), the tanker being rotatably connected with that device for rotation about a vertical axis (4,117). A conduit (6,24,25,45,46,122-125) extends upwardly towards that device (5,11,20,61,74,95,111,135) and towards a swivel (38,58,79,102,121) concentric with that axis (4,117) and from the swivel towards the tanker, the system having a quick connect coupling (83,84,85,91,92,97,116,117,118). The device (5, etc.) preferably has controllable buoyancy and can be of any type including a normal mooring buoy.