Rail wheel set and car

A rail wheel set (2) for a car (1) movable on a rail (9) of a rail system (12), comprising a bearing housing (6) having a wheel suspension configured for connecting the rail wheel set (2) to the car (1), and two running wheels (4, 5) rotatably mounted on the bearing housing (6), each of the wheels having a respective rail rolling surface (41, 51) shaped to match a contour of a running surface of the rail (9), and a respective ground rolling surface (42, 52), wherein the wheels are configured to roll independently of one another on the running surface (91) of the rail (9) or on a floor, wherein the rail rolling surfaces each have an inner edge and an outer edge, wherein the ground rolling surfaces (42, 52) are each integrally formed in one piece with the outer edge of the respective rail rolling surfaces (41, 51), and wherein the rail rolling surfaces configured to be arranged on the rail together with the inner edges of the rail rolling surfaces facing each other, with the ground rolling surfaces to the outside.