Piton

Repeated hammering and extraction of pitons damage the rock, and climbers who subscribe to the clean climbing ethic avoid their use as much as possible.

[1] Pitons are still found in place (as "fixed" pitons) on some established free climbing routes, as fixed belay station anchors, in places where nuts or cams do not work; and are used on some hard aid climbs.

From small to large, the most common are:[5] Early pitons were made of malleable iron and soft steel and would deform to the shape of a crack when hammered into the rock, which worked well in the irregular cracks found on European limestone.

During the exploration of the hard granite in Yosemite Valley in the 1950s and 1960s, it was found that soft pitons did not work well.

John Salathé pioneered designs using hardened steel which were much tougher than the European pitons.