Bromo Tengger Semeru

Bromo Tengger Semeru National Park has sub montane, montane and sub-alpine ecosystem types, with big trees that are hundreds of years old. In Addition, there are about 137 species of birds, 22 species of mammals, and four species of reptiles in this park. Bromo Tengger Semeru National Park is the only conservation area in Indonesia that has a sand 'sea'. This unique feature covers a total area of 5,250 hectares at an altitude of about 2,100 m above sea level.

Beneath the sand sea, seven eruption centres have been found along two intersecting lines, one from east to west and the other from northeast to southwest. From this northeast-southwest line emerged Mount Bromo, an active volcano which intermittently emits smoke and ash, and is an ever-present threat to the lives of some 3,500 peoples living below. The crater of Mount Bromo has a diameter of about 800 metres from north to south and 600 metres from east to west. Most of the area within a radius of 4 km from the crater centre is considered hazardous.

A total area of Bromo Tengger Semeru National Park is 50,276.2 hectares, geographical location is 112o47' - 113o10' East and 7o51' - 8o11' South.

The national park is named after its two mountains, Mount Semeru (the highest in Java at 3,676 m asl), Mount Bromo (the most popular) and the Tengger peoples who inhabit the area.

Temperature are refreshingly cool during the day but outright cold at night as temperatures can drop close to zero in the summer and are rarely much above 5o C in winter. Daytime temperatures anywhere in the park never exceed 20o C with low teens being normal. It can rain at anytime and the mean average rainfall is 6,600 mm. Most of that comes in the wet season though November to March. During periods of heavy rain in January and February especially, many part of the park are inaccessible due to flooding. Landslips are also a real issue at these times.

Mount Semeru, also known as Mahameru ('Great Mountain'), is one of Indonesia's most active volcanoes. What stands out most about this mountain is the fact that it erupt periodically (and very reliably so). Every 20 minutes or so, the volcano belches out a huge cloud of steam and smoke, sometimes interspersed with ash and stones. Climbing Mount Semeru requires some planning and a permit from the national park authority. The mountain is often closed due to its highly active nature.

Mount Bromo (2,329 m asl) is easily recognized as the entire top has been blown off and the crater insied constantly belches white sulphurous smoke. It sits inside the massive Tengger caldera (diameter approximately 10 kms), surrounded by the 'Laut Pasir' (sea of sand) of fine volcanic sand. The overall effect is unsettlingly, unearthly, especially when compared to the lush green valleys all around the caldera.

The Tenggerese peoples that live around the park are indigenous to the area and adhere to ancient Hindu beliefs. According to legend, the ancestors of the tribe were members of the Majapahit kingdom who went to exile. Strangely, despite being aware of the potential dangers of Mount Bromo, the local people seem unafraid. 

The same goes for the visitors who come to the park in great numbers, particularly around the time of the 'Upacara Kasodo'. The Upacara Kasodo (Kasodo Ceremony) is held every year (December/January) at the full moon. Through this ceremony, the Tenggerese invoke the blessing of the deities to ensure an abundant harvest, to be spared from calamity and to be cured of various diseases. To earn such blessings, they climb down the sides of the crater to catch the offering thrown into the crater by other members of the community above. The scramble for some of the participant to tumble down to the crater's floor.

Declared by Minister of Forestry No. 278/Menhut-VI/1997, May 23, 1997.