Yarlung Zangbo Grand Canyon in China's Tibet is the largest and deepest canyon in the world. It is 504.6 kilometers long, with an average depth of 2,268 meters and a maximum depth of 6,009 meters. The scenery here is magnificent, but the environment is harsh. Many areas are still untouched in the canyon, making it a secret land on Earth. Glaciers, cliffs, steep slopes, debris flows and billowing rivers crisscross the entire region, where abundant hydropower resources are stored, and endangered ancient species also thrive.