For endurance swimmers, The Oceans Seven Challenge is a big goal as it is a marathon across seven open water destinations and a big accomplishment. It includes the North Channel, the Cook Strait, the Molokai Channel, the Strait of Gibraltar, the Catalina Channel, the Tsugaru Strait, and the English Channel.
At that point, Walker had already gone through two of these destinations (the Gibraltar Strait and the English Channel), so he thought he would be logical to have this as the next challenge. But at that point he didn’t realise how challenging and dangerous it could be, so it was a bit of a shock in the end.
