A maelstrom (// or //) is a very powerful whirlpool; a large, swirling body of water. A free vortex, it has considerable downdraft. The power of tidal whirlpools tends to be exaggerated by laymen. There are few stories of large ships ever being sucked into a maelstrom, although smaller craft are in danger and tsunami or sinkhole-generated maelstroms may even threaten larger craft. Tales like those by Paul the Deacon, Edgar Allan Poe, and Jules Verne are entirely fictional.
One of the earliest uses in English of the Scandinavian word (malström or malstrøm) was by Edgar Allan Poe in his story "A Descent into the Maelström" (1841). In turn, the Nordic word is derived from the Dutch maelstrom, modern spelling maalstroom, from malen (to grind) and stroom (stream), to form the meaning grinding current or literally "mill-stream", in the sense of milling (grinding) grain.
The original Maelstrom (described by Poe and others) is the Moskstraumen, a powerful tidal current in the Lofoten Islands off the Norwegian coast. The Maelstrom is formed by the conjunction of the strong currents that cross the straits (Moskenstraumen) between the islands and the great amplitude of the tides.
In Norwegian the most frequently used name is Moskstraumen or Moskenstraumen (current of [island] Mosken).
The fictional depictions of the Maelstrom by Edgar Allan Poe and Jules Verne describe it as a gigantic circular vortex that reaches the bottom of the ocean, when in fact it is a set of currents and crosscurrents with a rate of 18 km/h.
The maelstrom of Saltstraumen is the world's strongest maelstrom and is located 10 kilometres (6 mi) south-east of the city of Bodø, Norway. Its impressive strength is caused by the world's strongest tide occurring in the same location. A narrow channel connects the outer Saltfjord with its extension, the large Skjerstadfjord, causing a colossal tide which in turn produces the Saltstraumen maelstrom.
The Corryvreckan is the third largest whirlpool in the world, and is on the northern side of the Gulf of Corryvreckan, between the islands of Jura and Scarba off the coast of mainland Scotland. Flood tides and inflow from the Firth of Lorne to the west can drive the waters of Corryvreckan to waves of over 9 metres, and the roar of the resulting maelstrom can be heard 16 kilometres away.
A documentary team from Scottish independent producers Northlight Productions once threw a mannequin into the Corryvreckan ("the Hag") with a life jacket and depth gauge. The mannequin was swallowed and spat up far down current with a depth gauge reading of 262 metres with evidence of being dragged along the bottom for a great distance.
Other notable maelstroms and whirlpools
Old Sow whirlpool is located between Deer Island, New Brunswick, Canada, and Moose Island, Eastport, Maine, USA.
Naruto whirlpool is located in the Naruto Strait near Awaji Island in Japan.
French Pass (Te Aumiti) is a narrow and treacherous stretch of water that separates D'Urville Island from the north end of the South Island of New Zealand.
Tsunami and Sinkhole-generated maelstroms and whirlpools
Tsunamis generated by large earthquakes have historically formed ephemeral whirlpools at points along the area of wave impact, dependent upon submarine topography. Most notably, the tsunami from the 2011 Tohoku earthquake created a maelstrom off Oarai, Ibaraki Prefecture, which was videotaped during news coverage and has become a viral video.
Lake Peigneur is located in the U.S. State of Louisiana 1.2 miles (1.9 km) north of Delcambre and 9.1 miles (14.6 km) west of New Iberia, near the northernmost tip of Vermilion Bay. On November 20, 1980 a drilling disaster took place and the lake temporarily drained into a large sinkhole. The resultant whirlpool sucked in the drilling platform, eleven barges, many trees and 65 acres (260,000 m2) of the surrounding terrain. 
In literature and popular culture
Three of the most notable literary references to the Lofoten Maelstrom date from the nineteenth century. The first is the Edgar Allan Poe story "A Descent into the Maelström" (1841). The second is 20,000 Leagues Under the Sea (1869), the famous novel by Jules Verne. At the end of this novel, Captain Nemo seems to commit suicide, sending his Nautilus submarine into the Maelstrom (although in Verne's sequel Nemo and Nautilus survived). The "Norway maelstrom" is also mentioned in Herman Melville's Moby-Dick.
In Spanish and other languages, maelstrom is used as a synonym for whirlpool. Hence, the word "maelstrom" appears in diverse contexts metaphorically to make reference to different subjects or objects that suggest great chaotic or sinister forces. The word maelstrom is used to denote powerful, inescapable destructive forces.
The main characters, Edward and Elizabeth, in Giacomo Casanova's 1788 novel "Icosameron" are sucked into a maelstrom which acts as a portal to the Protocosmos.
In the Disney film Pirates of the Caribbean: At World's End, the freed sea goddess Calypso causes a gigantic maelstrom that the Flying Dutchman and the Black Pearl have to navigate in order to position themselves to fire on each other.
- MythBusters Episode 56: Killer Whirlpool. Mythbustersresults.com. Retrieved on 2011-10-26.
- 10 Magnificent Maelstroms. WebEcoist. Retrieved on 2011-10-26.
- Paul the Deacon, History of the Lombards (8th century AD); Edgar Allan Poe, "A Descent into the Maelström" (1841); and Jules Verne, Twenty Thousand Leagues Under the Sea (1870).
- The Merriam-Webster new book of word histories. Merriam-Webster, Inc. 1991. p. 300. ISBN 978-0-87779-603-9.
- Encyclopædia Britannica, 1958 edition.
- B. Gjevik, H. Moe and A Ommundseb, "Strong Topographic Enhancement of Tidal Currents: Tales of the Maelstrom", University of Oslo, working paper, 5 Sep 1997. A condensed version published as Gjevik, B.; Moe, H.; Ommundsen, A. (1997). "Sources of the Maelstrom". Nature 388 (6645): 837–838. doi:10.1038/42159.
- "Equinox: Lethal Seas". UK and US co-production by Northlight, "Lethal Seas" UK Channel 4, "Sea Twister!" US Discovery Channel, covers several notable maelstroms.
- "Why Japan's Tsunami Triggered an Enormous Whirlpool". Fox News. 11 March 2011.
- Video of 2011 Tohoku tsunami whirlpool, Youtube
- Lake Peigneur sinkhole disaster on YouTube
- Herman Melville Moby-Dick Chapter 36, Wikisource.