Two famous free-solo rock climbers: Steph Davis and Alex Honnold on sheeting joints in Zion national park and in Yosemite national park (‘Thank God Ledge, Half-Dome) where Honnold made the first ever free-solo ascent.

Refer to Davis, 2013, and Honnold and Roberts, 2016 for some remarkable examples of planar sheeting joints. Rock and mountain climbing, as shown in countless internet sites, is a particularly rich source of examples of rock exposures at all scales, for those interested in rock fracture mechanics principles.

Free-solo climber Alex Honnold on El Capitan. Extension fractures in the third dimension are the ᴀssumed origin. Such features may be hundreds of meters in extent and seem to be formed by mountain-induced stress (and strain) rather than being a part of a pre-existing major joint pattern.