The Phong Nha Natural Reserve wasone largest special use forest with an area of 41,123 ha. Then PhongNha - Kẻ Bàng National Park was established under the Decision No189/2001/QD-TTg dated December 12, 2001 by the Prime Minister. TheNational Park was be inscription on the World Heritage List at themeeting 27th of the World Heritage Committee - UNESCO in Paris fromeJune 30th to July 5th 2003 on Criterion (viii) (former Criterion (i)-Earth's history, record of life, landform processes and features).

PhongNha – Ke Bang National Park is located in the middle of the AnnamiteMountain Range, 40km from Dong Hoi city, 500 km from Hanoi Capital, andclose to the Vietnam - Laos border to the west. Phong Nha - Ke Bangshares its boundary with Hin Namno Nature Reserve, PRD Laos to thewest, Minhhoa district to the north, Botrach district to the east, andQuang ninh district to the south. Geographical coordinates : N17021’12” to 17039’44”, E 105057’53” to 106024’19”.The area of theNational Park is 85.754 ha. The site is devided  into 03 functionalregions: the strictly  protected region: 64.984 ha, the ecologicalrehabilitation areas: 17.449 ha, the administration service areas:3.4114 ha.

Phong Nha- Ke Bang is a central biodiversity of Greater Annamites Eco-region,which has been identified as one of two hundred biodiversity centers inthe World (WWF, 2000). In addition, Phong Nha - Ke Bang have beenidentified as two of more than sixty Important Bird Area of Vietnam byBirdLife International (2005).

Temperature:The annual mean temperature is  23 - 25 degree celsius. The highesttemperature is in June, July and August, with mean temperature greaterthan 28 degree celsius. Daily variation in temperature is high, about10 degree celsius in summer and 8 degree celsius in winter.
Rainfall:Phong Nha - Ke Bang is situated in region of the high rainfall with anaverage of 2,000 mm to 2,500 mm per year. The highest rainfall isconcentrated in September, October and November.  The rainy season isfrom July to December . The dry season is from January to June and thelowest rainfall is in February and March.

Humidity: Mean annual relative humidity is 83 - 84%. In the period September toApril, humidity is highest (85-90%). The period  of May to Augustexperiences hot and dry northwesterly winds, so that humidity is lower.

Wind:The northeasterly winds and sometimes the easterly or southeasterlywinds appeared in the winter . In the summer a southwesterly wind iscommon, which sometimes  changes to a hot and dry northwesterly wind,in June, July, and August. The period from September to April, theeasterly and southeasterly winds sometimes come from the sea.

Hydrology:The flooding season takes place from September to November, with thelargest floods appearing in the middle of September and October.Besides the main rainy and flooding season, rains in May and Junesometime cause large floods. In the dry season, from February toAugust, almost all the streams in Phong Nha - Ke Bang become  “ deadstreams”. The water level in the Chay and Son Rivers is very low atthis time.

Topography:The endogenous and exogenous geological processes, which have occurredfrom Triassic up to now, have created the diverse topography andgeomorphology of the area: non-karst landforms, transitional landformsand Karst landforms. Karst landforms is characterized old tropicalkarst formed mainly in the Cenozoic, constituting 2/3 the area of thesite.

Geological and cave system development process:The geological structure here expresses the diversity and longdevelopment history of the earth's crust. The earth's crust hasundergone  several main development stages (from the Ordovician periodup to now) with 5 tectonic megacycles corresponding with the 5geological evolution stages of the world.

Vegetation: The National Park is 93.57% covered by forest, of which primaryforest covers 83.74% . The site  one of the highest percentage forestcoverage  in Vietnam. The  Park contains the diversity of ecosystemssuch as land mountainous ecosystem, karst ecosystem, river ecosystem.Vegetations and habitats have been developed for long time in thoseecosystems. So that there are eleven vegetation types and subtypes inPhong Nha - Ke Bang area

Biodiversity:Phong Nha - Ke has  global significance for biodiversity conservation.Based on the Scientific Reports, to date 2,651 vascular plant species,735 vertebrate animal species, 369 insect species have been recorded inPhong Nha - Ke Bang. Among of which 116 plant and 129 animal speciesare listed in the Vietnam Red Data Book and the IUCN Red List.