Surfing is often dismissed as a laidback activity, stereotyped by long-haired hippies who spend their lives sunning themselves on the beach. The reality, of course, is that it's one of the most demanding full-body disciplines around. And when the waves get really big, surfing can literally become a matter of life or death.
One such wave, off the coast of Nazaré, Portugal, is believed to be the biggest in the world. With the right conditions, it can swell to more than 100ft tall and break with terrifying speed and power. To catch a ride, surfers need to be towed in at full speed on jet skis, with their feet strapped into their boards. At the right spot, they let go of the rope and navigate their way
