An access platform system for enabling access to and from ground-based structures, vehicles, and mobile equipment. The system has a main frame with walls that is attached to or juxtaposed with the ground-based structures, vehicles, and mobile equipment; a vertical platform displacement assembly attached to the main frame; and a folding steps assembly. The vertical displacement mechanism has left and right intermediate carriage assemblies, and left and right lift cylinders with a multi-stage apparatus for influencing the stroke of the lift cylinders. In one embodiment, the folding steps assembly has an electromechanical means for folding and unfolding the steps.