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

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.