For more than two millennia now, an astonishing event has regularly manifested off the coast of Norway. Four times each and every day, a set of vortices open up in the waters of the county of Nordland. And according to experts, this phenomenon is the most powerful occurrence of its kind.
A little over six miles away from the Nordland region known as Bodø, a strait called Saltstraumen lies between two fjords. These are called Saltfjorden and Skjerstad Fjord. In simple terms, a fjord is a slim section of water, formed by a glacier, which is wedged between cliffs.
Measuring just under two miles in length and 490 feet in width, the Saltstraumen strait is by no means considered large. Yet even so, every six hours around 110 billion gallons of water surge through it. It is therefore known to possess one of the most powerful currents anywhere on Earth.