Bolt
An artificial anchor placed in a hole drilled into rock to protect either a lead climber or as a belay and rappel anchor. Most bolts used for climbing purposes are construction anchors, either wedge or sleeve bolts in either 3/8-inch or ½-inch diameter. A bolt hanger is attached to the bolt so a carabiner can be clipped to it. The use of bolts and drills in climbing is very controversial because it permanently alters and mars the rock surface. The placement of any bolt or the drilling of any hole should only be made by expert climbers that are well aware of both the legal and ethical ramifications of bolting. The placement of a bolt in rock should only be a last resort, and bolts should never be placed next to cracks where other removable protection can be used, which don’t damage the rock.A climber places a bolt at Shelf Road.