Saltstraumen is a strait with one of the strongest currents on the planet. Located in Nordland county, about 10 km (6.2 mi) southeast of Bodø, this short (3 km) and narrow (150 m) channel connects the Saltfjord and the Skjerstadfjord between the islands of Straumøya and Knaplundsøya. The tidal current in the strait is so strong that it pushes 400 million m³ of seawater through the strait with speed up to 37 km/hour. The currents form vortices up to 10 m in diameter and 5 m deep. One way to look at Saltstraumen is the Saltstraumen Bridge located on Norwegian County Road 17. The currents are the strongest in March and during the full moon every month.
Maelstrom means a "very powerful whirlpool." The Nordic word became international thanks to Edgar Allan Poe's story “A Descent into the Maelström.”
The current is formed when the tide moves towards the Skjerstad fjord. The height difference between the sea level and the fjord is almost one meter and the current speeds can be over 30 km/hour because of this difference. When the current turns, it's possible to go through the strait by boat and waters seem quite calm.
One of the most thrilling experiences in the Saltstraumen is snorkelling in the strait. Local companies offer dry suits, snorkel masks, and other equipment to experience the speeding away from the whirlpools.
For a detailed tide time schedule, check additional resources.