Longship
Longships for the most part used two different kinds of anchors. The most common was a natural wood yoke formed from a tree branch. The weight was supplied by a stone passing laterally through the U of the yoke. The top of the yoke was closed by either a length of hardwood or a curved iron head, which kept the stone in place. One side of the head stuck out so it could dig into mud or sand. In the Ladby ship burial in Denmark, a unique iron anchor has been found, resembling the modern fisherman's anchor but without the crossbar. The cross bar may have rusted away. This anchor—made of Norwegian iron—has a long iron chain to which the hemp warp was attached. This construction has several advantages when anchored in deep waters or in rough seas.
Traditional climbing
When a climber has reached the top of a climb an anchor must be set up to allow the leader to bring up the seconder safely. An anchor has a number of different components which should be put together in a redundant way to make the anchors safe.In some cases a traditional climb may be too difficult or there might not be enough time to complete the climb before dark. The lead climber may decide to abort the climb (or "bail") and descend to the ground before reaching the top. To do this an anchor is set up mid-climb and whatever protection that is required to ensure a safe descent is left on the rock after the climbers abseil to the ground.A number of types of rock are climbed on each with a varying degree of suitability for traditional climbing. Some examples are sandstone, granite and limestone.