Top-roping

Top rope climbing (or top roping) is a style in climbing in which the climber is securely attached to a rope which then passes up, through an anchor system at the top of the climb, and down to a belayer at the foot of the climb. The belayer takes in slack rope throughout the climb, so that if at any point the climber were to lose their hold, they would not fall more than a short distance.

Top-roping is often done on routes that cannot be lead climbed for one reason or another. Most top-rope anchors can be reached through non-technical means, such as by hiking or scrambling to the top of the cliff.

It is the most common style used at indoor climbing walls and is also used in situations where other methods would be unsafe or environmentally damaging. For example, in Kent and Sussex in south-east England, the sandstone rock is soft and prone to erosion, so placing protection into the rock would be both damaging and unreliable. There, top-roping from permanent anchors and solo climbing are the only forms of ascent allowed.

By contrast, in some other areas, top roping is frowned upon for various reasons – including possible erosion from people trying routes too difficult for them or a lack of suitable top-rope anchor points.

When selecting a rope for heavy top roping use, a large diameter (>= 10mm) static rope (or low-stretch rope) is recommended for the anchors to prevent rope wear and reduce rock erosion and to ensure maximum safety in the event of a fall. A dynamic rope should be used for the climbers. It is important to arrange the anchor system such that the climbing rope touches the rock as little as possible; damage to or destruction of the rope can result if a rope is loaded or dragged across sharp rocks enough times or with enough force. For anchors which are set back from the cliff edge, extending the anchor using multiple slings, a long adjustable-length sling, or a length of static line is common. Most practitioners run the climbing rope through two screwgate carabiners attached to the anchor, to provide backup in case one becomes undone. In the interests of safety at least two separate and redundant anchor points should be used, with forces distributed as evenly between them as possible. In the photo above, it can be seen that only the two locking carabiners protrude over the cliff edge, allowing the climbing rope a relatively free run from belayer to climber.

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Wikipedia