The Corryvreckan Whirlpool off Jura
The Corryvreckan Whirlpool lies between the Scottish islands of Jura and Scarba and is known for its fierce waters.
The whirlpool holds a strange allure for sailors and wild swimmers despite its channel being defined as unnavigable by the Royal Navy.
At slack water the torrents are benign disguising the dangers of the site.
At full strength the currents can reach over 10 knots, standing waves rear up and the whirlpool can be heard 10 miles away.
The Old Hag
The Corryvreckan Whirlpool is one of the largest whirlpools in the world. Tides from the east and west of Jura meet off the northernmost tip of the island where the Corryvreckan is located, funnelling in to the spot at great force. An underwater basalt pillar known as "The Old Hag" then forces the tidal water upwards, as the water smashes off the sides of the channel, resulting in the maelstrom that is the whirlpool.
According to tradition the Corryvreckan, or Coire Bhreacain, Whirlpool is named after Norse King Breachan. The King had to prove his bravery in order to marry a princess of the isles.
Breachan anchored his boat in the whirlpool to prove his courage, using three ropes - one made from hemp, one from wool and one from virgins' hair. On the third day of anchorage, after the hemp and wool ropes had broken, the virgins' hair rope gave way and Breachan was drowned.
Legend states that the rope made from hair failed as one of the maidens had been unfaithful.
Gateway to Hell
Corryvreckan has been compared to the gateway to Hell and sailors have drowned whilst trying to navigate a passage through the body of water.
George Orwell, who wrote "1984" on Jura had to be rescued from the clutches of the whirlpool in 1947 after a boat trip with his son, niece and nephew went awry. Orwell managed to get his boat to the small outcrop of Eilean Mor and was rescued by a fisherman.
The whirlpool is famous the world over and has been the subject of books, documentaries, plays and also played a dramatic part in Powell and Pressburger's 1945 film "I Know Where I'm Going" with Wendy Hiller as the heroine falling for the Laird of Kiloran (Roger Livesey) as nature and the Corryvreckan Whirlpool played their part.
Boat trips can be taken to view the whirlpool or it can be seen from dry land off the northern tip of Jura.