In June 2013 Sean Conway set out from Land's End in his bid to be the first person to swim the length of Britain. It was a challenge so extreme that not only had it never been attempted before, but most of the sponsors Sean approached turned him down as they were worried that he would die trying. Once in the water Sean had to develop incredible mental strength to deal with the extreme cold and hours alone. He also needed to devise ways to take on the huge number of calories he needed to sustain him. But Sean also swam with dolphins and seals and among stunning night-time phosphorescence. He had a unique view of the British coast, discovering tiny hidden coves and exploring shipwrecks. When there were problems with the support boat, Sean and his crew met many kindly people who were willing to come to their aid.