Arete vs Dihedral

An arete and a dihedral are opposite rock features. An arete is a convex outward edge or prow where two faces meet, climbed on the outside with balance and laybacking; a dihedral is a concave inside corner, like an open book, climbed between the walls with stemming and laybacking.

Aspect Arete Dihedral
Shape Convex outward edge Concave inside corner
You climb On the outside of the edge Between two walls
Key techniques Layback, flag, balance Stem, layback, jam
Feel Exposed, balancey Secure, bridgeable rests
Also called Arête, prow Corner, open book

It's an arete when…

  • The rock juts outward as an edge
  • You climb the outside of the prow
  • The line feels exposed

It's a dihedral when…

  • Two walls meet as an inside corner
  • You press between the two faces
  • You can bridge for a rest

Verdict

They're geometric opposites and demand different techniques — aretes reward balance and flagging on an exposed edge, dihedrals reward stemming and counter-pressure inside a corner.

Frequently asked questions

What's the difference between an arete and a dihedral?

An arete is a convex outward edge you climb on the outside of; a dihedral is a concave inside corner you climb between two facing walls. They're opposite shapes and need different techniques.

How do you climb each one?

On an arete you use the edge as a feature — laybacking and pinching it, flagging a leg to stop barn-dooring. In a dihedral you stem between the walls, layback a corner crack, or jam any crack, often finding rests by bridging.

What's a corner in climbing?

'Corner' is another name for a dihedral — an inside angle where two rock faces meet like an open book. It's climbed with opposing pressure between the two walls.

Related: Arete · Dihedral · Stemming · Lieback