The 32-year-old, who claims he is not a good swimmer, plans to swim 21 miles of the 900-mile trek every day – the equivalent of the English Channel crossing – and hopes to complete the voyage in eight weeks.
He will face difficulties from the cold, strong currents and illness through water getting into his ears, nose and lungs, as well as injury risk from sea creatures such as jellyfish.
His attempt is reminiscent of comedian David Walliams’ effort for Sport Relief in September 2011, when he swam the 140-mile length of the River Thames and raised more than £2 million for charity, despite falling ill with “Thames Tummy” – which caused a high temperature, sickness and diarrhoea – and damaging a disc in his back. Conway, who has so far raised £400 for the charity War Child, said he decided to attempt the epic swim because he wanted to come up with “a crazy challenge” that would inspire people to get fit and into swimming.
“When I found out swimming Britain had never been done it was a no-brainer,” he said. “It’s going to be the adventure of a lifetime and I’m going to get really fit too.”
Conway will start his challenge today, setting off from Land’s End at noon and swimming to Sennen Cove, a few miles up the coast – “where its easier to see me off”. At 2pm he will take to the water again to properly begin his journey.
He can only swim with the tide in his favour so will be in the water from 4am until 10am, resting until 4pm and then back in until 10pm. His meals will be liquid while he is swimming and he will sleep on the beach or a support yacht. He will also be GPS-tracked via a swimming website.
He said: “This will pinpoint the spot where I stop so I know where to carry on from the next day.”
After leaving Land’s End, Conway will swim up the west coast of the UK, around many Scottish islands. “I’ll work my way up the north coast of Devon and across to Wales. After going along the west coast of Wales, I will cut north to the Isle of Man and then on to Scotland,” he said.
“I will then make my way through and around the Hebrides before cutting east along the north coast of Scotland and finishing at John o’ Groats.”
He said he is looking forward to the Scottish leg of the journey most. “I’ll be at my fittest and the Hebrides are truly going to be spectacular. I can’t wait.”
Born in Zimbabwe, the author and photographer did his first endurance swim at the age of ten when he swam a mile across a lake. More recently, as well as having climbed Kilimanjaro dressed as a penguin, he completed the Three Peaks cycle challenge in a long weekend – cycling 140 miles a day and climbing Snowdon, Scafell and Ben Nevis – and rode his bike from London to the Alps.
Last year he set out to break the world record for cycling round the world, a 16,000-mile journey through 25 countries on six continents, but his dream was shattered when he was hit by a truck in the US.
Injury wasn’t enough to halt Conway in his tracks, however, and he pedalled the final 12,000 miles with a fractured spine to complete the trip in 116 days. But he reckons his latest challenge is going to be one of the toughest.
He said: “The hardest part will be dealing with my thoughts, looking into murky water and wondering what’s below.
“With many other endurance challenges, like running or cycling, you get to look at the scenery to keep your mind busy. I won’t have that. Who knows what I’ll do. I might go mad. Watch this space.”
Conway has not set a fundraising target but hopes to raise as much as possible for the African charity. He said: “No child deserves to be the victim of adults not getting along and creating war.”
He added: “I can’t wait to see Britain from an angle most people don’t get to see, from the sea. The landscape is going to be incredible.”
He is also extending an invitation for members of the public to join him on his travels, either in kayaks or swimming.
“I want this to be a big social adventure so come and get involved,” he said.