Building a multi-pitch anchor: judging placements, choosing series or equalised setups, keeping the angle small and checking the station properly.
An anchor is the point where everything in a multi-pitch route comes together: it holds you, your partner and, in the worst case, a fall. Four criteria make it good — redundancy (never a single point), load sharing across the placements, a small angle between the legs and no shock if one point fails.
The angle is the variable most people underestimate. At 60 degrees each of two placements carries about 58 percent of the load, and down to 50 percent at smaller angles — roughly half, as intuition suggests. Open the angle to 120 degrees and each point alone carries 100 percent (calculation: load ÷ (2 · cos(angle/2))). From there you are no longer distributing, you are doubling.
The honest answer to "is it hard?": the knotcraft is manageable, the judgement is not. You can build an anchor on two modern bolts after one course day. Judging questionable pitons, threads and cams takes years of experience.
Why it is worth it: in the review of 210 North American climbing accidents in one year, 100 happened on the ascent and 46 on the descent (46 with the phase unknown) [1] — on the descent a good one in five, in a phase where anchors and rappel stations often carry the load.
Checkable entry criteria before you build an anchor alone:
Look at each point separately: material, condition, surrounding rock, direction of pull. A rusty piton in crumbling rock does not get better from a second sling.
Milestone: You give your partner one sentence per point on why you trust it — or do not.
On two solid bolts, the series setup is today's standard method: the main load point carries, the second sits behind it as a backup [2]. If the points are individually less than fully reliable, you build a fixed load distribution (e.g. the South Tyrol anchor) so the load is shared; the formerly common free-running equalised anchor is considered outdated by the DAV because the master point slides through when one placement fails [4].
Milestone: You decide in under 30 seconds and can justify the decision.
Everything runs into one master point with a locking carabiner. The angle between the legs stays small — a common rule of thumb (practice value, not quantified in the DAV texts checked) treats 60 degrees as the target and 90 degrees as the ceiling. At 90 degrees each point already carries around 71 percent instead of the hoped-for half.
Milestone: You build five anchors in a row where your coach does not object to the angle.
Ask yourself with every build: what happens if one point breaks? If the master point then drops, the remaining placement gets a shock load — exactly the loading it likes least.
Milestone: On every build you can show how far the master point travels on failure. The answer: ideally not at all.
Four points, spoken and touched: placements, redundancy, angle, master point and locked gate. Then anchor yourself, then set up the belay.
Milestone: You run the check ten times in a row without skipping a point.
Anchor building is the point in this guide path where a mistake does not hit you alone but the whole rope team. So the rule is harder here than anywhere else: no course, no anchor of your own.
For context: according to an analysis of more than 400 studies, sport climbing has a low injury rate per climbing hour, lower than for example basketball or soccer; in alpine and ice climbing, injury rate and severity were higher [3]. The consequences on multi-pitch routes are in a different league than in the gym.
This guide explains and motivates, it does not replace supervised training. Have anchors shown to you in a multi-pitch course and get your own builds signed off repeatedly.
You do not need a protractor — you need geometry. If the distance between the two placements is no greater than the length of one sling leg, the angle is guaranteed to be 60 degrees or less. That follows directly from the isosceles triangle and works at any anchor, with any sling, without arithmetic.
Practically: if the bolts sit far apart, you need a longer sling — not more force, not more faith. The angle is the one element of an anchor you can control exactly.
Aim for 60 degrees at most, with 90 degrees as a rule-of-thumb ceiling (practice value). The reason is pure physics: at 60 degrees each point carries around 58 percent of the load, at 90 degrees about 71 percent and at 120 degrees the full load each. Beyond that you are no longer distributing, you are multiplying.
On two solid modern bolts the series setup is today's standard: simple and fast [2]. You use a fixed load distribution when individual points are questionable and the load genuinely has to be shared — so more on pitons and removable protection [4].
A build in which one sling is threaded through both placements and pulled together below. The triangle creates a wide opening angle and additionally pulls the placements inwards against each other — both raise the load per point considerably. Build two separate legs to a master point instead.
Two intact, modern bolts in solid rock are the norm on equipped multi-pitch routes and are considered sufficient when redundancy and angle are right. With visible rust, loose rock, old pitons or an unclear direction of pull you add a third point — that is experience-based practice, not a study figure.
Where you can belay in the direction of pull and in a comfortable stance — usually around chest height when standing at the station. Too low forces you into a bad position, too high makes rebuilding awkward. It also has to stay accessible when two ropes and two people are hanging on it.
Hand Jam & Crack Technique: Wedge, Don't Pull