length of a potential fall. The leader also may clip into pre-placed bolts. Indoor gyms might have short runners pre-attached to fixed anchor points in the wall. Unlike top-rope climbing, where the climber is always supported by an anchor located above the climber, lead climbing often involves scenarios where the climber will be attached to a point under him or her. In these cases, if the climber were to fall, the distance fallen would be much greater than that of top-rope and this is one of the main reasons lead climbing can be dangerous. The fall factor is the ratio of the height a climber falls and the length of rope available to absorb the fall. The higher the fall factor, the more force placed on the climber as the ropes decelerate them. The maximum fall factor is 2. It is often advised that climbers who are interested in lead climbing should learn from experienced climbers and participate in training sessions before lead climbing on their own. Multi-pitch The climbing rope is of a fixed length; the climber can only climb the length of the rope. Routes longer than the rope length are broken up into several segments called pitches; this is known as multi-pitch climbing. At the top of a pitch, the first climber to ascend (also known as the leader), sets up an anchor and then belays the second climber (also known as the follower) up to the anchor; as the second climber follows the route taken by the leader, the second climber removes ("cleans") the carabiners and anchors placed along the way in order to use them again on the next pitch. While "cleaning" the route, the follower attaches the carabiners and anchors to his or her harness belt loops. Once both climbers are at the top anchor, the leader begins climbing the next pitch, and so on, until the top of the route is reached. In either case, upon completion of a route, climbers can walk back down if an alternate descent path exists, or rappel (abseil) down with the rope. Sport The act of climbing single- or multi-pitch routes, protected by permanently-fixed bolts and anchors drilled into the rock, using a rope and the aid of a belayer. Unlike traditional rock climbing, sport climbing involves the use of protection (bolts) placed with power drills or on rappel or permanent anchors which are attached to the