Did you know the world's tallest mountain ranges were made by the same forces as the Marianas Trench? It's true. The Himalayas were made when two plates collided. The plates crumpled up, creating mountains. The fours biggest mountains in the world are in the Himalaya. The tallest is Mt. Everest, at 29,092 ft. The Himalayas are between India and China, and occupy Bhutan, Nepal, India, and Tibet. They are very dangerous as well. Many people have died in avalanches or falling into crevices.