Wheeled apparatus for use in loading and unloading load haulage vehicles has a support structure with linked side members (5, 10, 11, 110, 111, 210, 211) and a vertically movable platform (21, 120, 220, 320) carried on an upright structure (6, 115, 116, 215, 216, 315, 316) mounted on the support structure. The side members have ground-engaging wheels (8, 114, 214, 314) to enable the apparatus to be moved. One or more feet (14, 118, 218, 318) can be moved down into contact with the ground to hold the apparatus in position. The feet contact the ground together with the wheels so that the wheels contribute to stability. The feet and the platform may be moved by rams in the upright structure.