Indonesia is located along a complex convergent plate boundary. Kelimutu is a stratovolcano that has blown its top off, apparently several times, leaving behind a cluster of three beautiful caldera lakes. Each of Kelimutu's lakes is a different color, and the colors commonly change as circulation of water brings different materials to the surface. The yellow material in the lake in the foreground below is sulfur. The lake is a concentrated sulfuric acid solution.
Students like to ask if it is possible to go into the lakes.
The answer is yes. But you can't get out again. To see more volcano photographs, go to the Pagan Volcano page. There you can see photographs of an erupting stratovolcano from the Northern Marianas.