Category: mountain, craters, lakes Location: Bondowoso, East Java. Ijen Crater is the largest acid lake on earth at the top of Mount Ijen, has a height of 2368 meters above sea level with a depth of 200 meters and the area of the lake crater reached 5466 hectares. Crater in the territory of Nature Reserve Nature Trail Ijen Bondowoso, East Java. To reach Ijen, there are two main routes, ie from