Ijen volcano in East Java contains the world\’s largest acidic volcanic crater lake, called Kawah Ijen, famous for its turquoise color. The colours of the lake contrast with the sterile moonscape of the rest of the crater. Active volcano, constantly spewing sulfur smoke clubs, is incredible in its beauty blue fire and extremely hard working conditions in the sulfur mine. Sulfur combusts on contact with air to create stunning blue lava-like rivers of light in the Kawah Ijen crater.

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More than 3,500 feet in diameter with a 760-foot summit, Diamond Head in Waikiki is perhaps the world’s most recognized volcanic crater. It is a lasting remnant of a volcanic explosion that occurred about 500,000 years ago. Ancient Hawaiians called it Laeahi, which translates to “brow of the tuna.” The name “Diamond Head” can be traced to the 1800s, when British sailors mistakenly thought there were diamonds lodged in the crater’s soil. The extinct crater and lookout point at the peak of it is a popular hiking destination for many. A hiking trail leads from the crater up to a lookout point. But be prepared to climb some stairs. In fact, there are two stairs, one has 99 steps and a second one has 76 steps. There’s also a 225-foot (69 m) hardly lit tunnel through which you’ll have to go. The tunnel is a remnant of the former military use of the crater. So you should be in good physical condition to do the hike.

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credit: Eric Tessmer, Honolulu Hawaii

credit: Shiny Thing

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