A conveyor includes a first conveyor deck having a first plurality of contact elements, each having a contact surface movable around a closed path from a contact region to a non-contact region, the first contact regions lying in a plane or being bounded by the plane and a second conveyor deck having a second plurality of contact elements, each having a contact surface movable around a closed path from a contact region to a non-contact region, these contact regions lying in a second plane or being bounded by the second plane. The transport path of the conveyor is defined by the contact surfaces of the first and second contact elements in the contact regions, and the first plurality of contact elements are belts and the second plurality of contact elements are wheels.