We’ve found the 17 most otherworldly landscapes on the planet — you won’t believe they’re real. Expansive fields of sulfuric ponds make the Danakil Depression in Ethiopia one of the most inhospitable places for human life on the planet. China’s brightly colored Zhangye Danxia mountains were formed by 27 million years of red sandstone erosion. For more photos of the Marble Caves, click here »Salar de Uyuni in Bolivia is, at 4,000 square miles, world’s largest salt flat. Arizona’s Antelope Canyon is a surreal sandstone canyon formed by flash floods and monsoons over the course of millions of years.