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.
Offshore embedded anchors
Embedded anchors such as anchor piles (driven or drilled) are required for situations in which a large holding capacity is required. The design of anchor piles allows for three types of mooring configurations, vertical tethers, andcatenary and semi-taut/taut moorings, which allows for the mooring of different types of offshore structures, such as offshore wind turbines, FPSO, FLNG, etc. An industry example is the Ursa TLP which has been held on-station by 16 anchor piles of 2.4 m in diameter at 147 m long, weighing 380 tonnes each.