The country with the greatest elevation difference from sea level is Chile. This is largely due to the presence of the Andes Mountains, which contain some of the highest peaks in South America. One notable peak is Ojos del Salado, standing at approximately 6,893 meters. Chile also boasts the Atacama Desert, one of the lowest and driest places on Earth, with areas well below sea level. This extreme variation in elevation contributes to Chile's diverse ecosystems and geography, making it a unique area for scientific and ecological studies.