The double wheel consists of a road wheel and a rail wheel, both wheels being interconnected so that the so-equipped vehicle can be moved both on the road as well on rails. The rail running wheel has a smaller radius in relation to the road wheel so that the vehicle can run on the road unhindered by the rail wheel. Both wheels can be rigidly joined together or hydraulically movable independently of each other. Alternatively the rail wheel and the road wheel can be independently mounted.
