A support tower, particularly for a wind turbine. The support tower has at least a first elongated component which is internally hollow and at least a second elongated component which is slidably coupled to the at least a first elongated component and movable relative to the at least a first elongated component at least between a retracted position. The second elongated component is at least partially inserted in the at least a first elongated component, and an extracted position, where the at least a second elongated component is substantially extracted from the at least a first elongated component. A moving device for moving the second elongated component from the retracted position to the extracted position, and vice versa, and a blocking device configured to allow the at least a second elongated component to be blocked in the extracted position, are also provided.