What is the name of the largest canyon in the world?

In which country is the Tiger Leaping Gorge canyon located? In which mountain range is the Colca Canyon located? What is the name of the canyon in Arizona known for its Navajo ruins? In which country is the Cotahuasi Canyon located? Which canyon in Arizona, USA is known for its red rock? In which mountain range is the Samaria Gorge, a famous canyon in Greece? What is the name of the deepest canyon in the United States? What is the name of the canyon carved by the Rhine River in Switzerland?