How to see blue fire at Ijen crater?

For to see blue fire at Ijen Crater actually have 2 option :
Option 1 : You can departure from Banyuwangi at 11:00 am if you would like to see sunset and blue fire. 
Option 2 : You can departure from Banyuwangi at 00:00 midnight if you would like to see blue fire and sunrise.

The Blue Fire

The blue fire or blue flame phenomenon that there are only 2 in the world, one in Iceland and one in Ijen Creter. 
For To see blue fire the travelers can depart from Ketapang harbour or Banyuwangi at East Java. From that place you will drive to the starting point around 1.5 hours. And than you will do the trekking around 3 km, is not it and you will come down to the crater, the road to the bottom of the crater are very steep and hard about about 800 meters down to the crater. Only then, the blue flame pins. This amazing natural phenomenon. Blue flame at Ijen volcano is unique, rare, and becoming an attraction itself. It also adds to the beauty of Ijen Crater the after sunrise.

Sulfur Lake at sunrise time

Ijen crater complex is a group of stratovolcanoes, in East Java, Indonesia. It is inside a larger caldera, which is about 20 kilometers wide. The Gunung Merapi stratovolcano is the highest point of that complex. West of Gunung Merapi is the Ijen crater, which has a one-kilometer-wide turquoise-colored acid crater lake. The lake is the site of a labor-intensive sulfur mining operation, in which sulfur-laden baskets are carried by hand from the crater floor. The work is low-paid and very onerous. Workers earn around $5.50-$8.30 (Rp 50,000 – Rp 75,000) per day and once out of the crater, still need to carry their loads of sulfur chunks about three kilometers to the nearby Pultuding valley to get paid.

Ijen Crater from view point

Many other post-caldera cones and craters are located within the caldera or along its rim. The largest concentration of post-caldera cones forms an east/west-trending zone across the southern side of the caldera. The active crater at Kawah Ijen has an equivalent radius of 361 metres (1,184 ft), a surface of 0.41 square kilometres (0.16 sq mi). It is 200 metres (660 ft) deep and has a volume of 36 cubic hectometres (29,000 acre•ft).

Ijen Crater from view point

Suggestion :
Best moment to visit ijen for blue flame 00.00 am, because usually after 10 am up mountain is cloudy.

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