Poe went on to describe giant vortices, the likes of which he had never seen in person, but read about in legends. In reality, the maelstrom is not one massive whirlpool, but a series of smaller eddies created by changing tides. The term for these currents, “maelstrom,” derives from the Dutch, “maalen” (to grind, whirl) and “stroom” (stream). In Norwegian, they are called “moskstraumen” or “moskenstraumen” because they are particularly strong off the island of Mosken, reaching speeds of 5 meters per second (11 miles per hour).

Around the Lofoten archipelago in northern Norway, a large-scale wave of northbound water collides with the continental shelf, creating a regular tide. “The narrowing of the shelf from a relatively broad shelf south of Lofoten to a narrow shelf on the northern side of the islands [leads] to strong cross-shelf tidal currents near The Lofoten Point,” according to the authors of a hydrological study of northern Norway. The islands themselves also shape the waterflow in the area.