Natural Anchors

The first step in traditional climbing is learning how to set up top-ropes on climbs without fixed top anchors. Understanding how to build simple anchors using natural protection points allows you to climb in many areas without fixed anchors. The most common natural anchors are trees and boulders. Below is a suggested equipment list for building simple, natural anchors:

  • twelve oval or D nonlocking carabiners
  • at least three locking carabiners
  • six 24-inch sewn slings
  • two 48-inch sewn slings
  • two 6 mm by 24-inch prusik loops
  • one 10-foot knotted sling made of 1-inch tubular webbing
  • one 15-foot knotted sling made of 1-inch tubular webbing
  • one 20-foot knotted sling made of 1-inch tubular webbing
  • an extra rope (for areas where the anchor points are way back from the edge)
  • materials for padding the cliff edge

Next, we look at how to construct simple, natural anchors using a single large tree or block near the edge, or multiple trees or blocks near the edge, which might require the use of a second rope. Instructions for building these belay anchors follow this principle: All toprope anchors must be SECURE. You can be a 5.13 climber or the world’s greatest belayer, but if your anchor is not SECURE you are risking your life.

S – The anchor is strong enough.

E – The master point is extended over the edge.

C – The master point is centered over the climb.

U – The master point consists of an unbroken ring of metal.

R – The rope runs easily.

E – The edge is padded when necessary.

Strong Is the anchor(s) you have chosen strong enough? Trees should be at least 6 inches in diameter, alive, well rooted (trees growing on cliffs are notoriously shallow-rooted), and stable. Boulders and blocks should be really big, free of sharp edges, stable, and positioned so they cannot slip. If you are considering just one tree or boulder, is it really strong enough to be used by itself? Err on the conservative side. If there is any doubt, look for an additional anchor.

Extended Arrange the anchor so the master point is extended over the edge of the cliff. The master point is the main attachment point in a belay anchor-the point where all the individual anchor components come together. In a top-rope anchor, the master point usually consists of two carabiners that are opposed and reversed (see Unbroken, below). If you do not extend the master point over the edge of the cliff, the rope will be forced to run up and over the edge and back down again; it will not run easily, and you risk cutting it (ropes cut alarmingly easily under tension, even over the most benign-appearing edges).

Centered Be certain the master point is centered over the climb to minimize the climber’s potential swing. If the climb traverses (making it impossible to center the rope), then intermediate anchors will need to be placed along the route, probably on rappel-this complicates the setup considerably and unless you are confident in your ability to set up the top-rope safely, you should choose another route.

Unbroken The master point must be constructed so an unbroken ring of metal is created. Use a minimum of two carabiners with their gates reversed and as opposed to form a ring of metal as your master point. Single carabiners, whether locking or not, or multiple carabiners with their gates aligned the same way, can and do fail by coming unclipped. To set up carabiners reversed and opposed, clip them in from opposite directions (for example, one from the right, one from the left), so they form an X when their gates are both open, and then spin one around so that the gates are on opposite sides. Use two locking carabiners for extra security. Never compromise this principle.

Run The rope must run easily in order to ensure a sale belay. After you have determined that your anchor is strong, extended over the edge, and centered over the route, and you have created an unbroken master point, clip the rope in and test it to see if it will run freely. Make whatever adjustments are necessary to the system to ensure this. The rope must run freely to provide a proper belay.

Edge If you do everything correctly up to this point but fail to protect the edge, you have failed to create a SECURE anchor. Be quick to pad edges, even if they look fine. it does not take much to abrade a rope or sling-even rough rock without an obvious edge can be dangerous! Padding options include backpacks, clothing, finch tubular webbing, or lengths of old garden hose or fire hose.

Single Tree or Boulder

Trees make wonderful anchors, and it is a great day when you find a huge oak positioned perfectly over the climb, with roots buried deep in the bedrock.

But be careful with trees-looks can be deceiving. Before you use a tree as an anchor, be sure that it is:

  • alive-dead trees lose strength quickly as they rot or dry out
  • well anchored trees growing on cliffs are often rooted in shallow pads of forest duff, and even big trees can be unstable; look for roots extending down into the rock
  • big enough-6 inches is a good minimum size for use as a single-point anchor; smaller trees can be tied together in a multipoint anchor.

Boulders can also make great anchors, but they require extensive evaluation. Before you use a boulder as an anchor, check to see whether it is:

  • big enough-since boulders are not anchored by roots like trees, they must be big to be secure; 3 feet square is a good minimum
  • stable-even really big boulders can be unstable; check to be sure it cannot be rolled, slid, or tipped; if you have any doubts, pick another anchor
  • sharp-edged-be absolutely sure that no edge will damage the sling or rope that is wrapped around the boulder; pad edges as necessary
  • the right shape to hold the sling or rope slings cannot slip off trees, but they sure can slip off rocks; when you wrap the sling around the boulder, analyze the direction of pull and be absolutely sure that the sling will stay in place; if in doubt, use other anchors to hold the main anchor in place, or pick another main anchor

If you determine that a single tree or boulder will create a strong-enough anchor, the only question is how to tie it off. A girth-hitched sling is the easiest method. If necessary, several slings can be girth-hitched together to extend the anchor over the edge. Remember to adhere to all the SECURE principles. When relying on a single anchor, it is always a good idea to double up all the slings to build redundancy into the system.

Use good judgment when girth-hitching slings to trees, and consider leverage. If the tree is big, feel free to girth-hitch it at whatever height off the ground will make the anchor most effective. If the tree is small or you are at all concerned with leverage, girth-hitch it as close to the ground as possible.

Multiple Trees or Boulders

There are several options for creating a toprope belay using two or more natural anchors such as trees. Learning the fundamentals in the following systems will build a base of knowledge and allow you to safely innovate when circumstances demand.

Slings: Using slings long enough to extend over the edge of the cliff, girth-hitch one to each tree or boulder, bring the ends together, and clip in your carabiners to create the master point (remember to always tie into something when working near the edge of a cliff). If you are fortunate, the slings will center themselves over the route and they will be equalized.

If one of the slings is longer than the other, the system can still be equalized by clipping a carabiner to the shorter sling, clipping the longer sling into it, and then creating a magic X in the longer sling. Alternatively, a third sling can be clipped to each of the other slings with a magic X in it to create the master point. Remember that this system will fail if the sling used in the X fails so consider doubling it up.

Another way to equalize slings of unequal lengths is to simply tie an overhand on a bight in the long sling at the same level as the end of the short sling-effectively making both slings the same length. When the overhand knot is loaded, it will attempt to pull apart-do not worry: just tie the overhand neatly and tighten it well, and there will be no problem.

Separate climbing rope: If the anchors are too far from the edge for slings, a spare climbing rope can easily be used to form your anchor. One simple way to equalize this system with trees is to use a friction wrap.

First, tie the end of the rope to the first tree using a figure eight on a bight with a double fisherman backup knot. (To protect yourself while working near the edge, wrap a sling around the rope using a Klemheist or prusik hitch and clip it to your harness with a locking carabiner. Slide the sling up and down the rope as you move about while setting up the system.)

Next, run the rope down to the edge and tie in a figure eight on a bight master-point loop. Now run the free end of the rope back up to the second anchor and wrap the rope around the tree four to six times. Finally, tie a figure eight on a bight loop in the rope and clip it hack into the rope between the second tree and the master point with either a locking carabiner or two carabiners reversed and opposed-this closes the system.

If the anchors consist of two boulders, a good way to equalize them is to use slings or cordelettes to tie off each boulder. Clip one end of the spare climbing rope into the sling on one boulder with a figure eight on a bight with a double fisherman backup knot and either a locking carabiner or two carabiners reversed and opposed, tie the master-point figure eight at the edge of the cliff, and then run the rope up to the sling on the second boulder and clip it in with another figure eight on a bight using a locking carabiner or two carabiners reversed and opposed. You can fine-tune the position of the master point by feeding rope either in or out of the anchor knots.

If the anchor consists of three independent points that are far enough apart to require using a separate rope, then the following setup works well if it is three trees: Girth-hitch each tree with a sling. Tie a figure eight on a bight with a double fisherman backup knot into one end of the rope and clip it to the first anchor. Run the rope down to the edge, then back up, and clip it through the sling on the middle anchor, then back down to the edge, and finally back up to the third anchor and clip it in with a figure eight on a bight. You should now have a big W of rope.

Now go back to the edge, equalize the two bottom legs of the W, and tie a figure eight on a bight using all four strands of the rope for the master point. If the master point is not in the right position, untie the master point, untie the figure eight on the third anchor, take in or feed out rope as needed, retie the figure eight, and then retie the master point. This system equalizes each point, allows great latitude in the position of the final anchor, and creates a double-strand master point-bombproof!

On any of these top-rope setups, if the master point will be in contact with the rock while the rope is belayed through it, consider building redundancy into the system. If you built the belay using slings, consider doubling up the slings that form the master point. If you built the belay using a second rope, consider building a second figure eight on a bight.

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