Volcanoes aren't unusual in Indonesia, one of the world's most geologically active countries. Mt. Kelimutu, however, manages to stand out with its three crater lakes, each a different color. Adding to its kaleidoscopic appeal, chemical reactions spurred by volcanic activity cause the lakes to change color. What color and when remains unpredictable. The lakes are each about a thousand feet in diameter and are found at the eastern summit of Kelimutu. More photos...