A wind turbine having a nacelle being rotatably disposed on a tower is proposed. The nacelle has a first cavity, a generator housing portion disposed upstream to the nacelle having a second cavity, a hub disposed upstream to the generator housing portion with attached rotor blades at it having a third cavity. The first, second and third cavities communicates with one another. A rail-system has at least one rail-element having a device for lifting and/or transporting. The device for lifting and/or transporting is movable along the rail-system. The rail-system at least partially extends through at least two adjacent cavities.