Niah Caves is located within the district of Miri in Sarawak, Malaysia. Part of Niah National Park, the main cave, Niah Great Cave, is located in Gunung Subis and is made up of several voluminous, high-ceilinged chambers. The Great Cave lies in a large limestone block, about a kilometer long in general north to south direction and about half a kilometer wide, that is detached from the main Gunung Subis complex, by a valley between about 150 to 200 meters wide. The main Gunung Subis complex rises to about 394 meters above sea level at its highest point. The whole "Gunung Subis Limestone Complex" lies some 17 kilometers inland from the South China Sea coast and about 65 kilometers south west of the town Miri. It is roughly heart shaped measuring five kilometers from its northern tip to the south and four kilometers across. The Gunung Subis is surrounded by a low countryside with gentle hills from which the small limestone massiv and its smaller detached blocks rise rather appruptly out of the jungle, some with cliffs over 100 meters high. Though it is not an extensive cave system compared to others in Sarawak, it has been estimated to cover some 10 hectares and the roof rises to about 75 meters above the cave floor in some places. In geological terms, the limestones are part of the Subis Formation. This is dated to some 20 to 16 million years ago during the Early Miocene.

The cave is an important prehistorical site where human remains dating to 40,000 years have been found. This is the oldest recorded human settlement in east Malaysia. Painted Cave, situated in a much smaller limestone block of its own, some 150 meters from the Great Cave block's south eastern tip, has rock paintings dated as 1,200 years old. The caves are also well known for the birds' nest (Swiftlet) industry. It is a popular tourist destination in Sarawak.

Research was pioneered by Tom Harrisson in the 1950/60s. Since then local universities and foreign scientists have continued the archaeological research, and many articles have been published in the Sarawak Museum Journal. The site has been re-excavated (1999-2003+) by a joint British-Malaysian expedition to determine the accuracy of Harrisson's work.

Items found at Niah Cave include Pleistocene chopping tools and flakes, Neolithic axes, adzes, pottery, shell jewellery, boats, mats, then iron tools and ceramics and glass beads dating to the Iron Age. The most famous find is the human skull dated at around 38,000 years BCE. Painted Cave has paintings and wooden coffin 'death ships'.

Niah National Park was 31.4 km² when it was gazetted in 1974.

credited to wikipedia