Mount Rinjani is an active volcano in Indonesia on the island of Lombok. It rises to 3,726 m (12,224 ft), making it the second highest volcano in Indonesia. The first historical eruption occurred in September of 1847. The most recent eruption of Mount Rinjani was on 1 October 2004. The volcano and spectacular Segara Anak crater lake, are protected by a national park established in 1997. The 6 km by 8.5 km oval-shaped caldera is filled partially by a lake known as Segara Anak (approximately 2000m above sea level and estimated at being between 200m and 300m deep); the caldera also contains hot springs.
The eruptions of 1994, 1995, and 1996 have formed a small cone, Gunung Baru Jari or calls Mountain New – approximately 2300m above sea level, in the center of the caldera and lava flows from these eruptions have entered the lake.
The highlands are forest clad and mostly underdeveloped. The lowlands are highly cultivated. Rice, soybeans, coffee, tobacco, cotton, cinnamon, and vanilla are the major crops grown in the fertile soils of the island. Tourism is also increasingly popular with trekkers able to visit the rim, make their way into the caldera or even to make the more arduous climb to the highest point; fatalities, however, are not uncommon.
The park is popular for mountain climbs and trekking and represents an important nature reserve and water catchement area. The park is officially 41,330 hectares (159.6 sq mi) within the park boundaries and includes a further 66,000 hectares (250 sq mi) of protected forest outside. The mountain and its satellites form the Mount Rinjani National Park (Taman Nasional Gunung Rinjani). In 2008, the Indonesian government proposed to UNESCO that Mount Rinjani be one of the world’s official geoparks. If this was approved by UNESCO, Mount Rinjani would become the first such geological park in Indonesia.