Key takeaways
- An arête is a sharp, outward-facing edge of rock — a convex corner or rib.
- In climbing, it's the opposite of a dihedral (inside corner); you balance on and pinch the edge.
- In mountaineering, it's a narrow knife-edge ridge formed by glacial erosion — exposed and technical.
- Climbing an arête emphasizes balance, body tension, and clever use of the edge.
French 'arête' — fishbone, edge, or ridge.
What an arête is
An arête is a sharp, outward-projecting edge of rock. The word, French for ‘fishbone’ or ‘ridge’, describes a convex edge — and it carries two related meanings in the outdoors, one in climbing and one in the mountains.
The climbing feature
In climbing, an arête is a prominent outside corner or rib — the opposite of an inside corner (a dihedral). You climb the outside of the edge, balancing on it, pinching it, and using opposing pressure and body tension, which makes it a distinctive, technique-driven style.
The mountain ridge
In mountaineering and geology, an arête is a narrow, knife-edge ridge formed where glaciers erode a peak from two sides. These can be dramatically thin and exposed, with steep drops on both sides — serious, often technical terrain.
On a rock arête, a climber laybacks the sharp edge with their hands while smearing their feet on the faces to either side — fighting the tendency to barn-door off — in a balancey sequence that brute strength alone can’t solve.
How climbers tackle it
Whether a crag feature or a mountain crest, the arête rewards balance, body tension, and careful movement over power. On a knife-edge mountain arête, the same edge becomes exposed scrambling or climbing with serious consequences.
The bottom line
An arête is a sharp outward edge — in climbing, a convex corner or rib you balance on and pinch (the mirror of a dihedral); in the mountains, a glacier-carved knife-edge ridge that's exposed and serious. Both reward balance, body tension, and careful movement, making the arête one of the more elegant and committing features in the vertical world.
Frequently asked questions
What is an arête in climbing?
In climbing, an arête is a prominent outside corner or rib of rock — a sharp, convex edge that juts outward, the opposite of an inside corner (dihedral). Climbing one typically involves balancing on the edge, pinching it, and using opposing pressure and body tension, since you're climbing the outside of a corner rather than tucked into one.
What is an arête in mountaineering?
In mountaineering and geology, an arête is a narrow, knife-edge ridge of rock formed when glaciers erode a mountain from two sides. These ridges can be dramatically thin and exposed, with steep drops on both sides, making them serious, often technical terrain that demands careful movement and sometimes roped travel.
How do you climb an arête?
Climbing a rock arête rewards balance and creativity: you might pinch or layback the edge, use opposing pressure with hands and feet on either side, smear on the faces, and keep your body tension to avoid 'barn-dooring' (swinging off the edge). It's a distinctive, often elegant style of climbing that emphasizes technique over brute strength.
Sources
- Rock features & climbing — American Alpine Club
- Glacial landforms — USGS