The Bromo Tengger Semeru National Park covers some 800 square kilometers in the centre of East Java. It is the largest volcanic region in the province and there stands Mt. Semeru, which rises 3676 meters above sea level. At its northern end is the spectacular Tengger Caldera, Java's largest, with its 10 km barren desert-like sea of sand. Within the caldera rise the deeply fissured volcanic cones of Batok and Bromo, the latter is still active with a cavernous crater from which smoke blows skyward. Temperatures at the top of mount Bromo range about 5 to 18 degrees Celcius . To the south is a rolling upland plateau dissected by valleys and dotted with several small scenic lakes, extending to the foot of Mount Semeru, a towering grey forest-skirted cone dominating the southern landscape. 
Tengger sandy area has been protected since 1919, and its believed to be the only conservation area in Indonesia, even probably in the world possessing a unique ocean and sand at the attitude about 2000 m above sea level. There are several mountains inside the calderas namely: Mt Watangan (2,661 m asl)., Mt Batok (2,470 m asl), Mt Kursi (2,581 asl), Mt Watangan (2,661 m asl), and Mt Widadaren (2,650 m asl).
On the fourteenth day of the Month Kasada, the inhabitants of Tengger Mountain range gather at the rim of Mount Bromo's active crater to present annual offerings of rice, fruit, vegetables, flowers, live stock and other local produce to the God of the Mountain, as adherents of religion combining elements of Hinduism and Mahayana Buddhism the Tenggerese ask for blessing from the supreme God, Sang Hyang Widi Wasa. This ceremony called Kesodo Ceremony.
While the Great Mountain or Semeru offer a wonderful place to 3 days hike. Serenity of small lakes and large meadows, a three hours struggling through loose screw to the peak and breathtaking views from peak Semeru explodes every half hour and sends billowing smoke upwards. These gases and belching lava make Semeru dangerous " stay well away from the vent. The fine scenery and bracing climate, easy access and reasonably visitor-oriented facilities make this one of the most popular reserves in Java.
Bromo Tengger Semeru can be reached by private and public vehicle. There are four gates to access the place, Probolinggo, Wonokitri, Ngadas and Lumajang. Probolinggo approach is the easiest and by fat the most popular route, especially if you go by public bus, Wonokitri is the closes and the easiest one if you go by private vehicle from Surabaya (5 hours journey). To get closer to Mt. Bromo you must rent 4x4 vehicles (there are many 4x4 vehicles rental there).
There are a few options that you can choose to stay. You can stay at The Bromo Guest House which is located at Ngadisari that lies 3 km from the crater rim. Or you can choose other hotels at Cemoro Lawang because it this situated at the crater rim.
Walking on the sea of sand and stepping up on the 249 steps to rim is worth to try. Enjoying the unique crater in crater, watching the dawn at Bromo is the main attractions in the area.
Its kindly hard to find some food at night, because mostly of warung are closed after 7.30 pm. If youre in Wonokitri area, theres some warung in Tosari market, which still open at 7-9 pm.
There are many souvenir shops around Mount Bromo viewpoints who are selling T-shirts, scarf that are made from wool and others. There are also street hawkers who are selling these things too at the caldera area.
You can moving around on foot and normally it will takes 2 hours, or you can ride a horse or even rent a jeep (for this two, you are suggested to ask first and make a negotiation)
- Necessities for the trip include a torch, warm clothing, comfortable trekking shoes, and glove as a protection against the freezing temperature which hovers between zero to five degrees Celsius (33 to 41 degrees Fahrenheit).
- If you buy or rent something please Bargain.
- Sunrise starts at 5.00 am till 6.00 am (If werent cloudy), so you may leave from your hotel or guesthouse at 3 am or even less than that.
- Before start trekking, hiking or climbing, be sure that you already eat, or you can bring some food and drink from your places of stay.
- Otherwise, you can buy some food and drink on the nearest markets for your supply before you start your activities on mountain.
- If youre come in the right time, you may possible to watch the annual ceremony of Kesodo.
