In theory, a pitch length is limited by the length of the rope used (a fact that explains the frnch term for a pitch: Longeur). In practice, however, the leader more often than not, cannot climb pitches that use the full length of the rope, because of rope drag (friction on the rock and in the passing of the rope/ropes in protection binners. The drag become more irritating as the climber progresses through the pitch.
The same term is also used to denote the belays on the route. For example, the belay at the end of the sixth pitch is also called the sixth pitch.
Contributions to this page were made by Mica Yaniv and others...