Abstract: An elevator comprises an elevator car, a counterweight, a drive and a support, wherein the support couples the elevator car and the counterweight with the drive so that the elevator car and the counterweight are movable in opposite vertical directions by the drive, and wherein the support has a support section at the car side and a support section at the counterweight side. The elevator further comprises a sensor line which is coupled to both the elevator car and the counterweight and which is guided so that in the case of movement of the elevator car and the counterweight in opposite directions it generally remains tensioned by a substantially constant tension stress. The elevator further comprises a sensor which is coupled with the sensor line so that slackening of a support section is detectable by the sensor.