From Siberia to India, the Andes to the Arctic, and from deathtraps and vital lifelines to playgrounds for thrill-seekers, this episode explores the planet's extreme roadways. Across the world roads are vital lifelines. Witness mountains blasted to keep roads open, the worlds worst traffic, and a one-lane road with a 1900 foot drop, known as Death Road. These are the 10 most extreme roads in the world.