taken from: http://en.wikipedia.org/wiki/Kawah_Putih
Kawah Putih lake (7.10° S 107.24° E) is one of the two craters which make up Mount Patuha, an andesitic stratovolcano (a “composite” volcano). Mount Patuha is one of numerous volcanoes in Java. Kawah Putih crater lake itself represents a relatively stable volcanic system with no records of significant activity since around 1600.
The Kawah Putih site was opened to visitors in 1987. The lake is 2,430 meters above sea level so the local climate is often quite chilly (temperatures are frequently around 10 degrees celsius). This makes a brisk change from the humidity of the north Java plain and the capital city of Jakarta. Kawah Putih is a sizeable highly acid lake (pH 0.5-1.3) which changes colour from bluish to whitish green, or brown, depending on the concentration of sulfur and the temperature or the oxidation state. The sand and rocks surrounding the lake have been also leached into whitish colours through interaction with the acidic lake waters (with possible mineral precipitation as well).
The surrounding area is heavily forested. There is a pathway down to the lake which is surrounded by the high walls of the crater nestling into the side of Mt Patuha. The smell of sulfur is strong because there is a good deal of steam and sulfurous gas bubbling from the lake. There are tracks around the lake and through the nearby forest including to the peak of Mt Patuha. Visitors can walk around the crater area or sit in the various shelters. Local plants not widely found in lower altitudes in Java include javanese Edelweiss and Cantigy (Vaccinium varingifolium). Animals and birds which may be spotted include eagles, owls, monkeys, mouse deer, and forest pigs. Panthers, leopards and pythons have also sometimes been seen in the nearby forest.
A range of simple facilities exists near the lake. There is ample parking and public toilets. Entrepreneurial vendors sell trinkets and food. The site is well-signposted. Local farmers often take the opportunity to sell strawberries (widely grown in the area), steamed corn, and various other items such as pumpkin seeds (pepita).
Kawah Putih and the surrounding area (where there are resort facilities such as hot spas) is a popular spot for people from Bandung. On weekends and on holidays, quite large numbers of Indonesian tourists visit Kawah Putih. The site is so far less well-known to international tourists. According to Perhutani staff at the site, up to 10,000 people might visit on busy holidays and the total number of visitors is perhaps 300,000 per year.
Access is gained from the left of the main road travelling south by entering the park and proceeding along a 5 km access road. Travel time from the centre of Bandung, depending on traffic in and around Bandung, is perhaps two hours. The turnoff from the main road to Kawah Putih is hard to miss: there is a large signboard to the left of the main road and a prominent entry gate. The entry facilities and the crater location are well-managed by staff from the state-owned forestry firm Perhutani.
The main road is the busy road south from Bandung through the town of Soreang, the capital of the Bandung District, continuing down through the crowded Pasir Jambu township. Minibuses ply the route southwards from Bandung and, depending on traffic, can take up to two hours to reach the entrance to the Kawah Putih area.There are many thousands of small market-crop farmers in the fertile valley to the south of Bandung which leads up towards the Kawah Putih area. Local food-crops grown include a wide range of fruits and vegetables. A strawberry industry is well-established in the area and many strawberry farms have fruit for sale along the side of the highway.
Accommodation is available at various hotels in the Patuha area close to the nearby town of Ciwidey and also in Soreang.