Device and method for offshore arranging of a wind turbine or components thereof

A device for offshore arranging of a wind turbine or components thereof on a vertically extending foundation present at sea, comprising:

• an elongate superstructure connected releasably to the foundation and extending between a lower surface and an upper surface thereof in the vertical direction from the foundation, wherein the superstructure comprises an internal space which is accessible to a tower section of the wind turbine and in which the tower section can be received;
• a horizontally displaceable supply structure for a tower section, wherein the supply structure is configured to move a tower section coupled thereto from outside the internal space into the internal space by a horizontal displacement;
• and
• an engaging structure, received for vertical displacement in the internal space, for a tower section received in the internal space, wherein the engaging structure is configured to lift an engaged tower section in the internal space by a vertical displacement, whereby sufficient space is created under the relevant tower section for receiving another, underlying tower section in the internal space.