The present invention relates to an apparatus for providing access to equipment or structures that require maintenance. More particularly, the present invention is suitable to provide access to equipment or structures located offshore, such as wind turbines or structures for oil and gas production. The apparatus comprises a deck, an apparatus structure for supporting the deck, a platform and a platform support mechanism. The platform is movable with respect to the deck from a stowed position to an extended position. In the extended position the platform forms an extension to the deck. The platform support mechanism comprises at least one cable and at least one compression post. The/each cable has a cable first end attached to the platform at or adjacent to a platform leading edge and a cable second end attached to the platform at or adjacent to a platform trailing edge. The/each compression post supports the cable between the cable first end and the cable second end and is adapted to maintain a substantially constant tension in one of said cables as the platform moves from the stowed position to the extended position.