Whirlpools and tidal wonders

As the mighty whirlpool of Corryvreckan features on Countryfile this month, James Fair reveals some of the many astonishing marvels wrought by the tides around the British Isles

- James Fair

A colossal eddy that looks as if someone has just pulled the plug on the seas surrounding the Inner Hebrides, the Corryvreckan whirlpool is a freak of nature that spawns like a poisonous toad on a rising tide between the islands of Jura and Scarba.

From the Norse king Breacan who, legend has it, drowned in the whirlpool after trying to impress a local princess - to George Orwell's entanglement with it in 1947 while he was living on Jura writing Nineteen Eighty-Four, the whirlpool holds a distinctive place in Scottish culture.

The nature writer Roger Deakin considered attempting to swim across the Gulf of Corryvreckan (the strait between the two islands) when he was writing his classic work Waterlog. Approaching it on Jura, he describes in the book how he could hear the maelstrom before he saw it, sounding like "a low-pitched, continuous seething of brawling waves". It was 300 metres offshore, and within its circumference was a "mêlée of struggling white breakers... headbutting one another". Deakin backed out, saying an attempt would have been suicidal.

The first person known to have swum the Corryvreckan was, in fact, Orwell's brother-in-law Bill Dunn, who had spent some time living on Jura. Smeared in sheep fat, he completed the swim in 1949, despite having only one leg. It took him about half an hour.

The adventure tour group Swimtrek.com has run open-water swimming tours that take in a crossing from Jura to Scarba. According to Swimtrek's Jack Hudson (who has swum it himself), this can only be done safely at slack tide and when wind speeds are low. Even then, there are unusual currents that can be nerve-racking, he says.

"If you jumped into the maelstrom at full force, you would be sucked down and disappear very quickly," Jack says.