A trailer includes a load-bearing carrier frame which is guided on an undercarriage and includes a lateral longitudinal member and two cross members protruding at right angles from either end thereof. Between these, a central member is secured to the longitudinal member, parallel to the cross members, and a loading opening is formed opposite said longitudinal member. A lifting device is arranged, for mutual height adjustment purposes, between the carrier frame and the undercarriage. A load-clasping gripping unit may be arranged on the central member and may be displaced in the transverse direction between the longitudinal member and the loading opening.