Below photographic impression is part of the geology section of Nusa Penida concerning Kentung Cave, named after Pak Kentung - owner of the land on which the cave is located - Adegan Kawan, south of Ped, Nusa Penida. These caves are common on Nusa Penida and a delight to discover. The underground Nusa Penida Karst landscape, typical for the island, is best observed here. Kentung Cave offers a wonderful view to the interior of the caves formed in the Pleistocene limestone soil of Nusa Penida.

Karst is an area with a topography characterized by mostly limestone, with crevices, wholes and caves that were formed by the dissolution of a layer of soluble bedrock by rainwater or the water from rivers. Rainwater, as soon as it falls on the soil, immediately seeps into the ground leaving behind a dry surface. Karl Helbig was the first scholar to write an article on the Karst Cone Landscape so typical of Nusa Penida in 1941.

The geology of Nusa is very different from the great part of volcanic Bali but similar to its southern peninsula, the area of Bali commonly know as Bukit. All three islands have a limestone base and typical karst topography. The karst effect is particularly pronounced in Nusa Penida where a significant number of caves are found.

Climate (Giambelli, 1995)

The islands lie close to the equator and are subject to the west and east monsoon cycle. As in Bali, the year is basically divided into two periods: a first period that runs from the end of April or beginning of May, (sasih jesta according to the Balinese lunar calendar) to the end of September (sasih katiga) characterised by a hot and dry climate called masan panes.