Some people might only dream of adventure, but for others, there's no option but to explore the most extreme places on Earth. From the deepest caves to the roughest oceans, from the North Pole to dizzying heights on a high wire — what drives adventurers to constantly push themselves to the brink of human endurance? TED speakers share their experiences of going to the edge of our world.
Explorer Ben Saunders talks about what it takes to become a polar explorer. Engineer and daredevil caver Bill Stone describes what it's like to descend into the deepest caves in complete darkness for days on end — and why he keeps doing it. A former management consultant, Roz Savage holds four world records for ocean rowing, including being the first woman to row across three oceans alone. She explains why she's rowing across the Pacific. High-wire artist Philippe Petit tells the story of his 1974 tightrope walk between the Twin Towers and explains his lifelong fascination with pushing himself to the limit.
Explore more or listen again to this week's episode.