Gunung Rinjani is a mountain located on the island of Lombok, West Nusa Tenggara. Mount which is the second highest volcano in Indonesia with 3,726 m above sea level and is located at a latitude 8º25 ‘LS and 116º28’ BT is a favorite for mountain climbers Indonesia because of the beauty of the landscape. This mountain is part of Mount Rinjani National dariTaman which has an area of approximately 41,330 ha and proposed the addition so that it will be 76,000 ha to the west and east.
Administratively, the mountain is located in the territory of three districts: East Lombok, Central Lombok and West Lombok.
Segara Anak crater lake with a mountain Barujari lakeside views from the summit of Mount Rinjani on the east side.
Mount Rinjani with the highest point 3,726 m above sea level, dominating most of the views of the northern part of the island of Lombok.
On the west side there is a cone of Rinjani caldera with an area of approximately 3,500 m × 4.800 m, extends towards the east and the west. The caldera there are Segara Anak (immediately = sea, lake) area of 11,000,000 square meters with a depth of 230 m. Water flowing from this lake forming a very beautiful waterfall, flowing through a steep ravine. The Segara Anak many carp and tilapia are so frequently used for fishing. The southern part of the lake is called Segara Endut.
On the east side of the caldera are New Mount (or Mount Barujari) which has a crater measuring 170m x 200m with a height of 2296-2376 m above sea level. This small mountain last active / erupting since May 2, 2009 and during May, after previously erupted anyway in 2004.   If the eruption in 2004 no casualties, the eruption in 2009 has claimed the lives of 31 people indirectly , due to flash floods in Kokok (River) Tanggek by the pressure of lava to Segara Anak.  Earlier, Mount Barujari ever recorded erupted in 1944 (and establishment), 1966, and 1994.
Besides Mount Barujari there are also other craters that never erupted, called Mount delegation.