Simul Climbing: An Advanced Rock Climbing Technique

Simul climbing is an advanced style of multi-pitch climbing that involves rock climbers moving simultaneously while tied to the same rope. Gear that experienced pitch climbers might include in their simul climbing kit include auto-locking carabiners, ropes, and additional trad climbing gear (traditional climbing gear).

Climbers also call the simul climbing technique “climbing with a running belay.” A running belay refers to a climbing technique that uses friction to keep a climber from falling. There are various belaying techniques, many of which involve the assistance of a special belay device. While belaying, the belayer acts as a brake, attaching to the climber’s harness through a carabiner (or “biner”) and stopping a climber from falling if they lose their grip. However, subsequent members of the climbing team can belay by creating tension as they hold the rope for the climber ahead of them.

You can better understand simul climbing by comparing it to traditional climbing. In simul climbing, rock climbers ascend simultaneously following a tie-in to the same climbing rope, whereas in traditional climbing the individuals take turns and do not share a rope in the same way.

In traditional multi-pitch climbing, a team of two people (a leader and a follower) ascends, stopping at different belay stations. The lead climber inserts into the terrain pieces of protection, such as a belay or camming device, with the follower removing each piece as they pass by it—but the two climbers are not connected to each other. If one climber makes an error, they should be the only climber who falls, as all climbers are tied into different protection points.

In the simul climbing technique, the process is similar, with a runout of approximately fifteen meters between the climbers. A runout is the length of rope between a climber and their last piece of protection in the boulder—for example, a short runout would equal a short fall if the climber should make an error. If simul climbers come off the rock wall, there is a possibility they could pull another climber off the rock, resulting in second falls or even other follower falls. While a simul climb is safer than a free solo climb, it is not usually safer than traditional multi-pitch climbing.

Simuling is an advanced technique that beginner climbers must work up to learning. Experienced ascenders can use it to move more quickly with their team over long routes, big walls, easy terrain, or geography they know well. Here are some of the advantages of the technique:

1. 1. Maintains speed: A speed climbing team uses only a rope for progress since utilizing belay equipment would add time to their ascent. With simul climbing, the team can also downclimb quickly by way of a simul rappel, moving in a coordinated rhythm.
2. 2. Optimizes efficiency: The simul technique can be more efficient for moving over terrain with a group of experienced climbers. The climbers make upward progress simultaneously rather than waiting for each climber to take their turn. Simul climbing teams can also descend as a unit, more or less, by simul-rappelling off the wall and down to the ground.
3. 3. Reinforces teamwork: Simul climbing teaches great teamwork skills to climbers who are learning the technique. For advanced climbing teams, simul climbing makes use of their combined climbing knowledge to cover a lot of rock wall in a short period of time.

Simul climbing can enable a team of advanced climbers to make upward progress efficiently and in good time; however, it comes with disadvantages related to its inherent risks.

1. 1. Involves a high degree of danger: When you’re the second climber in a team of simul climbers, you must catch the leader’s weight if they fall. If the second climber falls, the leader must hold themself, the second climber, and the climbing gear—potentially without the use of protection gear if the leader fell before placing the next point of protection. Additionally, if the lead climber secures any placed protection devices improperly, the climbers could find themselves essentially free soloing while tied to other people—doubling each person’s chance of falling if one person makes an error.
2. 2. Requires perfect coordination: Simul climbing can create complications for the leader and follower or followers if there are any missteps in coordination or communication. While the leader manages placing gear, a follower must keep an eye out for rope drag, rock falls, excessive slack, and other unexpected forces climbers could encounter if they move at different speeds or fail to communicate.
3. 3. Stresses equipment’s integrity: Simul climbers frequently use progress capture devices (PCD), which enable climbers to take tension off a rope—such as when taking a break—without the weighted load slipping or sliding down or backward. The PCD prevents the follower from giving the leader slack or lowering them without transferring the load, which can make it a time-consuming process if a leader needs to move down the rock or back up in special cases. Use of PCDs can be complicated, as these pieces of equipment can damage the rope sheath if you use them improperly. Additionally, icy conditions can cause them to fail. A PCD can also potentially sever the rope entirely under specific conditions if a leader falls.

Climbing is a high-impact activity with an elevated risk of serious injury. Practice, proper guidance, and extensive safety precautions are essential when attempting a climbing pursuit. This article is for educational and informational purposes only, and is not a substitute for professional instruction or guidance.

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