The Saltstraumen whirlpools (maelstroms) has the strongest tidal current in the world. Up to 400,000,000 cubic metres (520,000,000 cu yd) of seawater forces its way through a 3-kilometre (1.9 mi) long and 150-metre (490 ft) wide strait every six hours, with water speeds reaching 22 knots (41 km/h; 25 mph). Vortices known as whirlpools or maelstroms up to 10 metres (33 ft) in diameter and 5 metres (16 ft) in depth are formed when the current is at its strongest. Сальтстраумен - одно из сильнейших в мире приливных течений (Бодо, Норвегия). Maelstrom