Abstract: This invention concerns a drilling installation comprising a base which rests on the ground, a rig, a winch, items of equipment such as a drill-pipe storage coffer, and a working floor which is raised above the base, surrounding the rig.The installation is characterized by the fact that it comprises a carrying platform designed to take the rig, and which can be moved from a low position in contact with the base to a high position, and which is connected by a suitable lifting device to lifting uprights attached to the base. The platform also carries the working floor and items of equipment.The invention more specifically concerns drilling installations for oil-drilling operations.