A hydrocarbon mooring and transfer system (2) includes a tower (3) resting on the seabed (4), a vessel (1) containing hydrocarbons, anchoring elements including at least four spaced-apart anchoring members (12, 13, 14, 15) connected via a respective anchor line (21, 22, 23, 25, 26, 27) to the vessel (1), a hydrocarbon transfer duct (6) extending between a coupling position (7), located between the bow (20) and stern (24) of the vessel (1) and the tower (3). The system including at least six anchoring members (12, 13 14, 15, 16, 17, 18, 19), at least four of which are connected to the vessel (1), the vessel being attachable to at least two different groups (12, 13, 14, 15; 14, 16, 17, 18; 15, 16, 18, 19; 12, 13, 17, 19) consisting of four anchoring members in at least two orientations.
