Kaeng Krachan was declared as a national park on 12 June 1981. Covering an area of 2914 km² it is the largest national park in Thailand. The park is located in Phetchaburi and Prachuap Khiri Khan Provinces, bounded by the Tanintharyi Nature Reserve along Myanmar’s border to the west. The park is not only part of the rainforest area north and south of the park in Thailand, but also part of a huge continuous rain forest complex deep into Myanmar covering 30,000 km².
Kaeng Krachan National Park is famous for dense morning mist covering the park with hill tops sticking above mist cloud around December-March, creating a spectacular view.
Possibly Thailand’s top bird- and butterfly-watching location, over 420 species of birds has been observed in the park boundaries which is the highest number of bird species in any national parks in Thailand. There are 57 known species of mammals and around 300 butterfly species. Some of rare birds that can be found in Kaeng Krachan areratchet tailed treepie, white-fronted scops owl, giant pitta, whooly-necked stork, great argus and grey-headed fish eagle. The park is also home to seven species of horn billsand all seven species of broadbills found in Thailand.
Wild mammals such as leopards, clouded leopards, bears, stump-tailed macaques,deers, elephants, bantengs, wild dogs, golden jackal, gaurs, crab-eating mongoose and many others are relatively common in the park, some frequently seen animals arelangurs, porcupines, civets, black giant squirrel, martens and gibons, many of frequently seen ones can be seen during a one or two days trip. There are also tigers in Kaeng Krachan but they are not common.
Phetchaburi and Pran Buri rivers are both originated from Tanaosri Ranges within the park. At the north side of the park, water streams drains to the Phetchaburi River which flows to Kaeng Krachan dam and flows all the way to Gulf of Thailand though Phetchaburi Province. At the south side the water streams drains to the Pranburi River, which too flows into a dam in Pranburi Province and finally to Gulf of Thailand.
Kaeng Krachan National Park covers a reservoir and mainly rain forests with rich flora and fauna. The highest elevation is a peak along the Burmese border at around 1500 meters, the second highest peak is Khao Phanoen Thung at 1,207 meters which is accessible by an overnight trekking from Phonoen Thung Camp Site.
Access to the main forest area of the park is limited to two roads, the road beyond Dan Khao Sam Yot Checkpoint (checkpoint is 19km from HQ) in the central parts, and one into the area around Pala U Waterfall in the south east.
Most visitors to Kaeng Krachan stays around the first campsite area next to the HQ where there is not much to see of the real wildlife the park offers. The real beauty of the national park starts approximately 19 km from the HQ at Dan Khao Sam Yot Checkpoint which is mainly a dirt road extending 36.5 km west through Ban Krang and Phanoen Thung campsites, only first 15 km until Ban Krang campsite is paved. Pala-U Waterfall at south edge of the park is a very popular attraction too, easily accessible from the nearby Hua Hin.