A climbing wall is an artificially constructed wall with manufactured grips for the hands and feet. Most walls are located indoors, and climbing on such walls is often termed indoor climbing. Some walls are brick or wooden constructions but on modern walls, the material most often used is a thick multiplex board with holes drilled into it. Recently, manufactured steel and aluminum have also been used. The wall may have places to attach belay ropes, but may also be used to practice lead climbing or bouldering.