I always wanted to be a pioneer swimmer - to swim in places where nobody had swum before. Much of my inspiration came from explorers like Roald Amundsen, Robert Scott, and Edmund Hillary. Twenty-four years on, I have now pioneered more swims around famous landmarks than any other swimmer, and I am the only person to have completed a long distance swim in every ocean of the world. But I'm probably best known for becoming the first person to undertake a long distance swim across the North Pole in 2007 and across a glacial lake on Mt Everest in 2010.
I am often asked why I do it. At a simplistic level, I am passionate about swimming and I enjoy pushing boundaries. But there's a lot more to it than that. Through my swims I have had a unique perspective on climate change. I have witnessed retreating glaciers, decreasing sea ice, coral bleaching, severe droughts, and the migration of animals to colder climates. It's as a result of these experiences that I am determined to draw attention to the fragility of our environment and to encourage everyone to take action.
But I've not always been in swimming trunks. I studied law at the University of Cape Town and the University of Cambridge, and then went on to work as a maritime lawyer in London. I now spend my time public speaking and campaigning to world leaders to protect the environment.
We stand at a critical point in the history of the planet and the steps which we take over the next few years will determine the future of the natural world and the sustainability of mankind.
I will never forget the first time I saw a polar bear. I was in awe of its absolute beauty. I realised at that moment that I may be one of the last people to see them alive. Their habitat is melting away rapidly with climate change.
By swimming in vulnerable ecosystems, I want to draw attention to the impact of our actions. They say that seeing is believing and it's certainly true. I hope that through my swims, and the filming and reporting of them, I can act as the eyes of the world. So, whether I'm swimming around islands which are fast disappearing due to rising sea levels, or swimming across parts of the Arctic which were previously frozen over, I will swim - and stand for the future of our planet.
I believe that each and every one of us can do something to ensure that future generations enjoy a safe and sustainable world.
To start, we can all make simple changes to the way we live
our lives - turning off lights, ensuring electrical appliances are not left on standby,
considering more carefully the cars we drive, reducing our air travel, buying local produce, and installing energy saving light bulbs. Let's also only vote for politicians who put the environment at the very top of the agenda and enact legislation that safeguards it.
Most importantly, now's the time to believe - to believe we can make the changes necessary to protect our environment - so we all have a future.
ARCTIC OCEAN
North Pole
July 2007 Swam 1km across an open patch of sea at the North Pole to draw attention to the melting of the Arctic sea ice.
World Winter Swimming Championships, Finland
February 2006 Won the Gold Medal in the 500 metre freestyle.
Verlegenhuken, Spitsbergen
August 2005 Broke the world record for the most northern long distance swim at 80º North, deep in the Arctic Ocean.
North Cape, Norway
August 2003 Became the first person to swim around North Cape, the most northern point of Europe.
ATLANTIC OCEAN
Sognefjord, Norway
August 2004 Swam 204km down Sognefjord the longest fjord in the world.
Cape Peninsula, South Africa
April 2004 The first person to swim around the entire Cape Penninsula, a distance of 100km.
Cape of Good Hope, South Africa
April 2004 The first person to swim around the Cape of Good Hope.
English Channel, England / France
August 1992 Swam across the English Channel from Shakespeare Beach in England to Cap Blanc in France.
Robben Island, South Africa
October 1991 Broke the speed record for swimming around Robben Island in a time of four hours and 10 minutes.
Robben Island, South Africa
May 1987 Maiden swim at the age of 17 when, swam from Robben Island to Blouberg Beach in Cape Town in three hours.
INDIAN OCEAN
Maldive Islands
February 2007 The first person to swim across the Maldive Islands to draw attention to the impact of rising water levels on low lying islands.
Nelson Mandela Bay, South Africa
January 2006 Swam 15km across Nelson Mandela Bay off Port Elizabeth in 4 hours 57 minutes.
Cape Agulhas, South Africa
May 1994 The first person to swim around Cape Aghulas, the southernmost point of Africa.
PACIFIC OCEAN
Sydney Heads, Australia
January 2006 The first person to swim from Manly Beach through the Sydney Heads to the Sydney Opera House.
Five Oceans
January 2006 The first person to complete the “Holy Grail” of swimming – a long distance swim in every ocean of the world.
SOUTHERN OCEAN
Deception Island, South Shetland Islands
December 2005 Swam 1 mile across Whalers Bay in Deception Island, the longest Polar swim ever completed.
Petermann Island, Antartic Peninsula
December 2005 Swam 1km off Petermann Island at 65° South to break the world record for the most southern long distance swim ever undertaken.
INTERNAL WATERS
River Thames, England
July 2006 The first person to swim the full length of the River Thames. It was undertaken when the river stopped flowing due to the drought, in the summer of 2006, to draw attention to the reality of climate change. The 350km swim took 21 days to complete.
Lake Malawi, Malawi
January 1992 Became the first person to swim across a great African lake by swimming 25km across Lake Malawi.
OTHER
Kayak into Arctic Sea Ice
2008 Paddled 140km in a surf ski (an open kayak) from the Island of Spitsbergen into the Arctic ice packs to draw attention to the continued melting of the sea ice.