Rock climbing is an activity in which participants climb up, down or across natural rock formations or artificial rock walls. The goal is to reach the summit of a formation or the endpoint of a pre-defined route without falling. Rock climbing competitions have objectives of completing the route in the quickest possible time or the farthest along an ever increasingly harder route. Rock climbing is similar to scrambling (another activity involving the scaling of hills and similar formations), but climbing is generally differentiated by its sustained use of hands to support the climber's weight as well as to provide balance.