Climb North America's Tallest Mountain Alone in January, Photo Lessons From Nat Geo's Finest, The World's Largest Gathering of Snakes, Carnevale in Italy

Summary: This week, we summit North America's tallest mountain alone in January; take photo lessons from one of National Geographic's top photographers; find the world's largest gathering of snakes in an unexpected place; know when to turn around on South Asia's tallest mountain; and celebrate "Carnevale" like an Italian.