<p>Dizzying heights, scorching deserts, arctic climes, rough seas and Amazonian jungles are the sort of obstacles you encounter
in the world’s toughest races. Here are some of the most extreme races in the world.</p>| <p>Dizzying heights, scorching deserts, arctic climes, rough seas and Amazonian jungles are the sort of obstacles you encounter
in the world’s toughest races. Here are some of the most extreme races in the world.</p> |